Larian Studios Forums Baldur's Gate III Baldur's Gate III - Story & Character Discussion The insane timeline of the main plot (do I even need to tell you that it's spoilers?)

1. Before the game starts - Moonrise Towers and the Emperor

We begin our story with the baldurian adventurer we get to know as the Emperor - in reality, he is legendary adventurer Balduran, but as this is never important to the story, I will continue calling him as the Emperor. While a highly successful adventurer, he longed for more and more. In his path of searching for glory, he arrived to Moonrise Towers around the year 1000, where he stumbled into a dormant Mind Flayer colony from the now long gone Illithid Empire, beneath the Tower - how and why such a colony wasn't discovered despite major constructions taking place in the local area, Moonrise Towers included, is unknown and likely boiled down to luck. Here, he was defeated and turned into a Mind Flayer against his will and got dominated by the local Elder Brain. However, thanks to the efforts of the dragon Ansur, an entity that can break hivemind communications at will apparently has freed Emperor, who in his panic tragically struck down the beast.

Now free and disguised, he returned to Baldur's Gate. It is important to know that the power of disrupting hivemind control at will belongs to two other characters in the plot next to Ansur, Gith and her son Prince Orpheus, one of whom is dead, and the other sealed within the Astral Prism by the Githyanki Lich Queen Vlaakith, which will come into play later. However, it is important to establish just how much Mind Flayers retain from their original personality. Jergal (Withers) confirms that Illithids do not have souls, as it is consumed in the process of ceremorphosis, yet Emperor goes on as if nothing had happened.

Eventually, Emperor raises the group known as Knights of the Shield to be the de-facto ruling faction in Baldur's Gate, keeping everyone safe and trade alive. Crucially however, he makes no attempt at mentioning the existence of the colony to anyone, including Stelmane who was his fiercest and most loyal ally. One could assume that it comes down to him "wanting more" - which is one of his greatest motivators that led him to Moonrise - therefore letting the colony roam free to be defeated once they become a more credible threat, but I think what he meant was that he simply wanted more power for himself, and was overall happy with becoming an Illithid. Nevertheless, he is now dubbed as the Emperor by the people - such was his influence.

How Balduran / Emperor survived this long is not understood. Balduran naturally should have lived until around 1100-1180, but he disappeared in the 1000s beneath Moonrise Towers and of course turned into a Mind Flayer. Technically, his age "reset" as now he was technically 0 years old as a Mind Flayer, and Mind flayers live up to about 125-135 years. Even if we assume that Balduran was turned into a Mind Flayer at the last possible second of his natural life, he would have only made it to the 1300s at the latest, and not to 1492 when the events of BG3 takes place - meaning that Balduran/Emperor lived nearly 500 years. A possible explanation could be that, while Mind Flayers do age, their projected life expectancy is more-so a death ritual that normal Mind Flayers in a hive experience as part of the Elder Brain making them promises of an afterlife, but in reality it is their memories and experiences being harvested. Therefore, it is possible that Emperor was broken free of the Brain before he was old enough to be consumed, and is now aging indefinitely until some sort of natural death occurs.

2. The Dead Three and their Chosen

Bhaal, God of Murder, Bane, God of Tyranny and Myrkul, God of Bones, known as the Dead Three, were dead between 1358 and 1482 (with a lot of ambiguity as to when they were active again, more on that later) as a result of the Time of Troubles. These three are all ambitious, cunning and manipulative, but they are also rather arrogant and foolish, which is why later on in the story they initiate the Absolute plot, something that the Jergal, the original God of Strife, Death and Dead confirms as being a stupid plan that would blow up in their faces. Nevertheless, time passes, but it seems as if the Three don't resurface when they are supposed to, not Bhaal at the very least.

Bhaal was supposed to resurface upon the death of Gorion's Ward, which canonically occurs in 1482, but the existence of Durge contradicts this. Durge was handcrafted by Him and Him alone, and Durge himself spent many, MANY years in worship of Bhaal before he met with Gortash in 1482. Just how many years is very foggy, as you get to customize everything about Durge in game, including signs of aging, but we can very easily assume at the very least 20 years, thanks to an interaction that occurs when a Heal spell is used on Durge, where a sudden memory of the Durge's childhood of playing games emerges. In this memory, it is hinted at that Durge at this time could have already been a murderer, but was yet to find their way to the Temple of Bhaal. The lowest age you can go in customizing is making your guy look somewhat like they're in their very late teens / super early 20s, however, the pre-made origin looks very mature, which is why my assumption is 20 years at the very least. When exactly Bane and Myrkul become active again, I don't know, but probably during or at least some years before 1482. The Temple of Bhaal was also quite active, as Orin was born and raised in there - how old she is, I have no clue of, but likely around the same age as Durge. Thus we can estimate that Bhaal was active again in 1462, despite the fact that it should be impossible. Durge was also a Chosen of Bhaal even before Gortash met him, and him being elevated must have happened before 1482.

Now, we can talk about Enver Gortash, whose name I already mentioned. Some time before 1482, Gortash, a corrupt Baldurian politican breaks free of the hold of Raphael, a powerful devil and the son of Mephistopheles. Now free, he seeks to gain power once more - aside him being a slaver and arms dealer, he also earns the favour of Bane, Lord of Tyranny, becoming his Chosen. In 1482 - the same year he sells Karlach to Zariel, and the same year the Dead Three are supposed to be ressurected - he is tasked with reuniting the Dead Three (with Bane's and the other God's motivations likely being wanting to get revenge and power over giving up a large part of their divine powers during the Sundering) and so he meets with Durge, Chosen of Bhaal. They quickly develop a friendship as they both understand that their predecessors failed due to a lack of unity and trust, however, they wouldn't reach out to Myrkul's Chosen just yet for reasons unknown. Instead, the two commit to stealing the Crown of Karsus and it's Netherstones from Mephistopheles, with the likely goal of Netherese magic making up for the God's lost divine powers. To do this, they visit Helsik, a vendor of devilish supplies and the one and only way for mortals to visit the Hells without devilish interference. Opening a portal straight to the palace of Mephistopheles, they steal the desired artifacts and make a quick exit.

However, next to the Crown laid a portfolio called "Accelerated Grand Design" which outlined the concept behind suspended ceremorphosis using an enhanced elder brain via the Crown of Karsus, and that this revelation sparked the idea of the Absolute plot. Note that Mephistopheles likely knew the risks of such a plan, which is why he didn't commit to it, but he kept the portfolio around anyways. Now returned from the Hells, the two needed to find an Elder Brain to put the Crown on, but also they had to accelerate getting Myrkul into the fray as well, as the three Netherstones were supposed to be wielded by three different persons, with the best candidates being the Chosen of course. Note: Gortash's motivations are somewhat foggy. In his room ingame, if you lockpick his Gilded Chest, you can find the Accelerated Grand Design document, which has this line written in it: "This Absolute, however, obeys the commands of the Chosen of the Dead Three - and needless to say, as Bane is the God of Tyranny, our allies who worship Bhaal and Myrkul must in the end defer to US." However, Gortash also did not lie about his relationship with Durge in Act3, and it will forever remain a mystery if Gortash was planning a last-second switcharoo, as even if you take his deal, he dies before he could do anything with it. However, given that Durge is motivated by his urges to rule alone in Act3, it is safe to assume that all three of the Dead wanted to rule alone by the end, as even Ketheric was planning betrayal, something he confirms at the end of Act2.

It is after this point that Gortash discovers the Emperor's true identity, likely now trying to find an Elder Brain to put the crown on leading him on this trail. The log "Shield Steward Interrogation Log Scroll or letter" outlines that Duke Stelmane was "not herself" and that she was eating the brain of an executed prisoner, and that the person being interrogated by Gortash was caught snooping around by something blue and floating, "but then it was just Stelmane, smiling". Then they don't remember anything afterwards. This seems like a giant plot hole, as the Emperor mentioned Stelmane as an ally, not as an Illithid, and the genders are very clearly distinguished - Stelmane is a female, Emperor is a male, and an Illithid Stelmane would have been dubbed the "Empress". Either that, or the Emperor was masquerading as Stelmane, but this is never mentioned by anyone, so it remains ambigious at best.

Nevertheless, Gortash achieves his goal - through the Emperor, he discovers the mind flayer colony beneath Moonrise, then they get in contact with the Myrkulite Necromancer Balthazar to ressurect Ketheric. Alongside Ketheric being the best candidate to become Myrkul's Chosen, he is also intimately familiar with everything in and around Moonrise Towers, and is also a highly accomplished General. Ketheric becomes Myrkul's Chosen in exchange for ressurecting Isobel, his daughter who he's infatuated with, then Gortash reveals the Emperor for who he is, drags him to Moonrise and has Durge put the Crown on the local brain, and the Chosen of the Dead Three dominate the brain using the Netherstones, and so begins the 10 years of setting up the Absolute.

2.1 Ketheric's source of invincibility

Originally in the 1300s, Ketheric was a Selunite Paladin who sired his daughter Isobel. She was the light in his life, and raised her as a faithful cleric of Selune. He was so infatuated with Isobel that when Isobel met Dame Aylin, an invincible angel of Selune, and the two quickly became lovers, Ketheric was quick to doubt Aylin, but otherwise tolerated her presence. However, Isobel tragically passed away (likely having been murdered, but it is never confirmed by whom), and in his desperation, Ketheric quickly converted to being a Sharran. In Shar's name, he became a Dark Justiciar and raised a massive army. A fantastic timeline of events was provided by Zerubbabel:
However, some time before Ketheric was defeated, he managed to trap Aylin in the Shadowfell. At latest this could have only occured in 1392, as Aylin claims in Act2 that she's been there for a century at that point. Then we jump to 1482 when Ketheric is ressurected and becomes the Chosen of Myrkul. Balthazar, likely by Myrkul's blessing, approaches Ketheric with the concept of a Soul Cage, something Ketheric could use to funnel Aylin's invincibility unto himself, which creates the following timeline:

-Ketheric traps Aylin in the Shadowfell but is not invincible yet, and then is promptly defeated in the early 1400s.
-Many years later in 1482, Ketheric is ressurected by the Myrkulite Necromancer Balthazar and tries to convince Ketheric to become the Chosen of Myrkul and to take part in the Absolute plot.
-Ketheric accepts on the only condition that his daughter is brought back as well. Isobel is ressurected, runs away, and he becomes the Chosen.
-Then they start putting in work to make the Absolute plot happen.
-At some point, Balthazar convinces Ketheric to create a Soul Cage around Aylin - they would have to physically go to Aylin and put her in the Cage.
-They collect the Four Orbs - whether they would have to go through the Gauntlet or if they would have to fight Yurgir is unknown. Shar would not open the door at will, as Ketheric has long forsaken Shar at this point.
-Now, Ketheric would want to seal away every bit of access to the Shadowfell and account for the smallest of disturbances (remember, he is a smart General person).
-Three Orbs are put back in the Gauntlet, and one ends up with Yurgir (somehow).
-The Spear of Night is never removed from it's resting place despite being the only weapon in existence that could kill Aylin, which would permanently remove Ketheric's source of invulnerability.
-In the event of Aylin breaking free and severing the invulnerability, baiting her to Moonrise Towers is the only way to have her reliably recaptured with some tentacle shenanigans.
-Ketheric can, at will, easily create another Soul Cage around Aylin, and does so in the final bossfight in Act2.

Unfortunately, this kind of falls apart, as Aylin, when you first talk to her, claims that nobody has visited her in a century, which is frankly impossible as the Soul Cage had to be put around her in the last 10 years somehow.

3. Spreading of the Absolute and the catalyst of an inevitable, unseen downfall

Now, with the Dead Three united, they can place the Crown atop the Elder Brain beneath Moonrise. Specifically, Durge places the Crown atop the Brain, which will quickly become important. With the influence of the Crown, they begin producing tadpoles infused by the netherese magic of the Crown, which grants them total and complete control over the tadpole, creating a state of "suspended ceremorphosis" where the tadpoles act as vessels for mind control. One unknown factor to Gortash and Ketheric was that the Brain itself - likely thanks to the netherese infusion - could have easily broken free if it so wished, but it began revering Durge and calling him it's master willingly. The Brain claims it is because Durge gave it "everything" and that his plan was devious, his cruelty unparalleled.

Now, it is important to remember that Gortash was the one who came up with the entire plan, Durge simply seeked to amass the largest bodypile ever known to man, so this comes off as if Durge became the leader among the Dead Three and has - for whatever reason - taken complete credit for everything. There is no reason to assume nor is there any indication that the Brain was lying at any point, so one can either assume that across this entire time of many years, the Brain simply never discovered the truth which it very easily could at any point, or that the Brain is simply an idiot and chose to follow the wrong master. It could also be that Durge was motivated from the start to rule alone as theorized earlier, and the Brain knew, and simply thought that the Bhaalspawn was the storngest and most ambitious of the Three. It is also not clear if Durge knew about him being revered, but it is more than likely that he knew. Either way, Durge is credited as the mastermind, and the Brain becomes subservient.

Nevertheless, their jobs are clear: Durge commits to a murderous spree on the streets of Baldur's Gate in the name of the Absolute, Ketheric begins raising an army of "True Souls" - people mind controlled by the parasites - under the banner of the Absolute to march on Baldur's Gate, and Gortash will be the one who "saves" Baldur's Gate as the desperate folk vote him into a position of total power. They all agree not to interfere with each others work in order to preserve trust, but also so they can work efficiently. It is agreed that in the end, they would all rule together - but as outlined before, the likelyhood of this was extremely small, and instead, only one would rule in the end. Either before or as they began this portion of the plan, Gortash reveals to the citizens of Baldur's Gate for what the Emperor is - a Mind Flayer, ruining the reputation of the Knights of the Shield permanently, and has him dragged to Moonrise Towers to be put under domination by the Brain once more.

Every piece of the plan was being put into position, until just before the game begins. Durge's sister, Orin - who, according to Orin, was seen as a faithful servant of Bhaal and looked upon with reverence by Durge - while both were in Moonrise Towers, betrayed him and fatally wounded him out of jealousy - specifically carving out Durge's brain, which crucially causes Durge to develop total and permanent amnesia later on in the story. She then promptly put a tadpole in Durge, looted his Netherstone and sent word to the other two Chosen that the Temple of Bhaal has appointed a new representative, leaving Durge to bleed out. Why Orin would tadpole a severely brain damaged Durge, and a Durge on the brink of death is unknown - unfortunately, her being crazy does not explain this, as if she were to torture Durge, she'd actually torture the tadpole instead.

Nevertheless, Durge is left to bleed out, but is then found by Balthazar's personal assistant, Kressa Bonedaughter. Always having wanted to experiment with the tadpole but never having been given the chance, she saves Durge to use him for her own twisted needs. According to Kressa, Durge's mind was so special that despite the tadpole, an entity that is supposed to facilitate total and complete mind control, he was able to form independent thoughts and retain some memory. Not long after, Balthazar finds out that his assistant is constantly being distracted by "her pet project" and gets so frustrated that, unknowningly, orders Durge to be tossed out.

Now, an important detail to remember here is that Netherstones lose control over the Elder Brain if their holder is slain. And there was a period of time where a Netherstone was not in control as Orin looted Durge, and yet the Brain was not acting up like it does in Act3. And if we similarly read ahead, in Act3, the Brain tells Durge and the gang that "The moment the tadpole was placed in your head, you became a pawn in my Grand Design." So, that means, that an Elder Brain, that never once lied about it's dedication to it's master has forsaken it in SECONDS. Like, the turnaround on this was so quick, for an entity that is otherwise a biological quantum supercomputer that it has me completely perplexed as to just why exactly would the Brain make that move, after an UNSUCCESSFUL assassination attempt. Even if not instantenously, but the moment Durge got tadpoled, and/or the moment Durge's Netherstone temporarily lost control, the Brain would have known that a terrible fate befell it's revered master. Why wouldn't the Brain lash out in rage, to save the one person that gave it, and I quote, everything? The entity that never once even entertained the idea of betrayal due to how much it looked up to him?

Instead, the Brain, on the spot, literally seconds after Orin turned her dagger on Durge, it decided that Durge is a "Disgraced Master" and a "Pawn in the Grand Design" - a Grand Design the Brain was yet to craft. Perhaps the single most confusing thing out of this entire ordeal is that the Brain did not hold the now tadpoled Durge on a leash, yet if we read ahead into the game, later on BOMBARDS Durge's tadpole with orders to "Follow my Chosen" and "Transform into a Mind Flayer". So why give a grace period? What changed? Was Durge not supposed to be a simple thrall in the end, a pawn? Did it want to ensure that Durge was to stay with Kressa so that Durge isn't tossed into a ditch, making sure that the other two Chosen don't find out about Orin's betrayal so that Durge can be put into the Nautiloid, only to then hinder it's own plan by letting Durge use the Astral Prism against the Brain (and again, while bombarding Durge with orders during that time)? Even if the previous question I proposed was intended to be answered, it wasn't, and in fact, there is no evidence, hint or reason to suggest anything else other than the Brain simply experienced a BSOD. Biological quantum supercomputer, mind you.

And let's just speak about Orin a little bit. It is well established that as a stark contrast to Durge, who views murder as the ultimate goal, Orin instead views murder as art. Note that if you do not play Durge origin, his corpse is promptly displayed in her bedchambers. However, if you play Durge origin, he is of course alive and well in the Nautiloid. Which prompts the question - as an artist, why would she forsake her greatest masterpiece, the cruelest of betrayals? Why would she leave Durge's body behind after brutally mutilating him? Wouldn't she burn Moonrise to the ground searching for the corpse of her masterpiece? While she isn't the sanest of characters, she has shown herself to be incredibly smart and intelligent when she needs to be - especially when it comes to murder and her art. So why is she being an idiot? And why isn't Bhaal doing anything about this? Wouldn't He want to punish such insubordination? Bhaal thrives on betrayals, but Durge was crafted to be the PERFECT Bhaalspawn after many failures over and over again - and he was just recently ressurected after one such massive failure, the Time of Troubles.

Sidenote: In the book "Elder Brain Domination" found in Ketheric's bedchambers in Moonrise in Act2, Ketheric hints that before the Crown was placed atop the Brain, the Bhaalists were already experiencing leadership struggles. However, this could have not been related to Orin replacing Durge, as the crowning happened in 1482, whereas the betrayal in 1492 (or at the very least, very shortly before the game began). I am not sure what to make of this revelation - it feels as if this is a leftover from early access, either when Durge's story was still in the works but unrefined, or some other completely different plot point that never made the final cut, or simply they forgot to cut this book out of the game or otherwise edit it to reflect accurate events.

Nevertheless, the Brain, now with it's master disgraced, begins crafting it's Grand Design. It began consipiring to turn the Dead Three against one another. To set the Grand Design in motion, the Brain reveals the existence of the Astral Prism to the Dead Three (which makes sense that it would know about it, given that the person inside caused the downfall of the Illithid Empire) in the form of dreams. Gortash specifically described it in his journal (called The Astral Prism Heist) as the following:


In a lucky turn of events, Durge is put on the exact same Nautiloid that Thrall Emperor is soon to pilot, and is soon to steal the Astral Prism. Again, this could be either lucky or intended by the Brain, unfortunately it's motivations are so foggy during this period that I simply can't definitely outline the mechanics of how Durge ended up on the Nautiloid. Nevertheless, this, Gortash's and Ketheric's general distrust towards Orin alongside future events (mainly the death of Ketheric) causes the three Chosen to fight amongst each other like children, exactly as the Brain intended.

One unforeseen development is that, somehow, the Sharrans of Baldur's Gate - Shadowheart included - catch wind of the Strike Team's plan, and at some point, either before venturing to the Astral Plane to steal the Astral Prism (somehow, I guess the Githyanki don't guard the front door, especially against Ghaik) or after the Nautiloid returned to Faerun, they sneak on board.

Before we arrive to the game's trailer and discuss the three Acts, I'd like to take a quick step back to point out another plot hole. It is established that Durge was tadpoled by Orin specifically. However, at the start of the trailer, the player sees Lae'zel and the player themselves being tadpoled. Therefore, canonically, Durge gets tadpoled twice. This makes absolutely no sense even if you wanted to turn Durge into a super soldier, as you would only be tadpoled multiple times if any extra tadpoles already collected the knowledge, experiences and powers of their previous hosts - aka. True Soul tadpoles. The trailer's tadpole however is a completely newborn one, therefore it makes no sense to be tadpoled by it.


4. Baldur's Gate III

And so we arrive to the game's trailer. Now, the timeline here is confusing at best, and I will attempt to structure it in the most coherent way possible. It is important to point out, that while the Mind Flayer who in the trailer tadpoles Lae'zel and Durge looks remarkably similar to Emperor, does not have the same eye colour as him (trailer one has orange eyes, while Emperor has purple eyes). Personally, I am still willing to accept that the Mind Flayer in the cinematic IS Emperor, mainly based on the fact that Larian forgot about the fact that Emperor is quite literally Balduran, and so has Emperor by proxy - but of course, the facts don't suggest so. Therefore, we can assume that Zerubbabel's first timeline is what is correct.


Once the game begins, Shadowheart posesses the Astral Prism, yet she is trapped in a Pod, now tadpoled. Therefore, the following must have happened:
1. Thrall Emperor's strike team successfully steals the Astral Prism from Vlaakith.
2. The Sharrans on board manage to get their hands on the artefact.
3. Thrall Emperor and his forces retaliate, either killing or putting the Sharrans in Pods. It is at this point, when Thrall Emperor holds the Prism in his hands that the Brain releases him, and so he becomes normal Emperor again. He assumes that it must be because the artefact did something to disrupt the hivemind communication, so he plants the artefact on Shadowheart, and enters it. Inside, he finds an imprisoned Orpheus that he can use to wield his power with will and precision.
4. In the meantime, the events of the trailer take place - the Githyanki catch up with the Nautiloid, the drive-by over Baldur's Gate and Avernus happens, Durge, Lae'zel and Shadowheart manage to make an escape back to Faerun - where, conveniently, the Githyanki don't follow them.
5. Conveniently, once Durge and the rest of the gang fall off the ship, they are the only ones that he saves with some levitation magic.
6. Whatever random adventurers he managed to gather, he guides in the guise of the Dream Visitor.

Alternatively, let's assume that the Mind Flayer in the trailer is Emperor, and the Mind Flayer that Durge shares a glance with before he gets knocked out of the ship is also the Emperor (despite the garment change). The following timeline must have occured in that case:
1. Thrall Emperor's strike team successfully steals the Astral Prism from Vlaakith.
2. As soon as Thrall Emperor is near the Prism, the Brain lets him go, giving him the illusion that the Prism is what disrupted hivemind communications.
3. Quickly gathering his bearings, he figures out he can enter the Prism and use Orpheus inside. He quickly leaves it, only to find himself and his crew in the middle of a Sharran ambush that he now has to defeat.
4. The Sharrans are either killed or put in Pods, ready to be tadpoled.
5. Trailer starts, the Emperor tadpoles several people he deems to be worth (by whatever standard).
6. He plays along all the way until Durge and the gang are knocked out of the ship, saves them with levitation magic, and then enters the Prism while they are KO-d.
7. He assumes the form of the Dream Visitor to guide his hand-picked adventurers on their journey.

Please note that both of these timelines are in italics, because there is no confirmation or details on just what exactly happened.

During their adventures, Emperor shows himself to the gang, posing as a Dream Visitor to convince them that he is the source of their protection (instead of posing as his actual identity of Balduran, despite most origins and possible characters being Baldurians, who live(d) in Baldur's Gate and are likely familiar, if not enthralled by the tales of the legendary adventurer Balduran), and that with this protection they can abuse the tadpoles to fight fire with fire, but always conveniently has to dip out when the gang demands answers out of him (which, in truth is him fighting Orpheus's Honor Guard, who were also imprisoned). Opinions between the companions vary from "ghaik lies" to "fuck yes" - given there is no negative consequence for having a tadpole, we can safely assume that the Durge goes along with it and gets even more tadpoles, despite looking for a healer/cure at the same time. Before we move on to Creche Yllek, I'd like to talk a little bit about Emperor, and just a little bit more about the Brain (which might seem repetitive).

Throughout this entire journey, Emperor has completely failed to use his persona as Balduran, something we know for a fact that he retained despite his mind, body and soul having been consumed. His characteristics are based on being the heroic adventurer type, even after having been turned into a Mind Flayer, and his goal is very clearly defined - he wants to rid the world of the Elder Brain and stop the Absolute plot. However, he constantly conflicts with such a clearly established goal. The writers wanted him to be everything - a person you can trust, a person you shouldn't trust, a person promising you power, a person who you can be friends with, your saviour, your slaver... your lover? It's presented in a way where the player is incentivized to distrust Emperor, - a very blatant relic of when Daisy was a thing that existed back in EA - but later on at the beginning of Act3, you get to use Detect Thoughts, and verify that EVERYTHING he is saying is sincere and true. So why would he make his own life more difficult? He has become an illithid, and with his experience to go with it, surely he must understand how to forge words like no other? Why is his CHA so low? Allow me to indulge myself and copy paste a simple fix for our boy that I made up not too long ago, a fix that would appear in the very first dream sequence.

"Another adventurer in the same boots as I was (actually giving the "I am just like you" line a meaning) - infected and powerless against the inevitable. My name is Balduran, and I am here to help you on your quest. The artefact you hold neutralizes the effects of Ceremorphosis, and I believe we can take advantage of that. These parasitic creatures are vessels for knowledge, experience and power. No doubt that on this path, you will stumble into many infected warriors. Extract their powers, and use them to your benefit. You may think that I am nothing more than illithid illusions, or you might think whatever else, but I will tell you this: keep that artefact close. It will be you and yours's salvation, and maybe, it yet be mine."
Of course, give it to an actual writer who crafts dialogue better than I do, but that should be the takeaway. That already establishes a strong foundation for Emperor/Balduran's character, because right now, Emperor is a bloody ping-pong.

And another little segment about the Brain, and a criticism that is of course Durge specific. Again, we must question why the Brain was so quick to turn on Durge. But let's assume a world that isn't completely insane and pretend that the Brain didn't forsake Durge. Allow me to copy paste a previous comment of mine once more. "You could even make it so that the Durge is special in that they don't need the Astral Prism to stay sane as the Brain goes out of its way to help Durge on his journey, trying to reunite with its master for an especially evil ending. There could be a real big conflict between Emperor and the Brain (you could even throw in Bhaal to the mix through Sceleritas Fel), putting an amnesiac Durge into an incredibly difficult circumstance. Given that'd require a significant rewrite and tons of dev work, but after playing games like DAO, different outcomes based on what origin you play is a standard I adopted." It would just simply make sense, and I feel like would clearly establish Durge as the main protagonist / antagonist of BG3, because, as said at the beginning of this post, there is none currently.

Anyhow, Creche Yllek time. Upon visiting the Creche, and all the events that take place within, the gang learns from a much annoyed Emperor (who forgot to account for the fact that he might not be trustworthy to others) that the Githyanki are after the prism because it would constitute the downfall of Vlakiith (because if the Githyanki were to find out that in truth, Vlakiith holds no power over the illithid, and that she simply desired to be a God, which is why she locked Orpheus away to make sure her rule can't be disuputed, all Githyanki would surely rebel and a coup d'état would be quick to follow), meaning that the gang now has to face two overwhelmingly powerful factions at the same time (which is not true, there is like one pack of Githyanki in Act2 and they fall like flies and an optional pack in Act3 if you search Emperor's old HQ) to retain the Prism, but it also serves as confirmation that the gang NEEDS the Prism else all is lost.

They are also joined by Jergal in the guise of Withers, the original God of Strife, Death and Dead. As to the why of it, Zerubbabel sums it up perfectly:

Now grouped up with the druid Halsin, who warns the gang about the Shadow Curse but fails to tell them that a Torch counters it, they visit the shadow cursed lands to get near Moonrise Towers. On their path, they conveniently run into the Harpers at Last Light's Inn, and an Isobel who ran away from her father Ketheric, knowing that he became something terrible (remember: the Harpers and Isobel were set up long ago, so lucky or convenient it might be, the mechanics work out). This Selunite cleric is quite literally the Last Light, keeping the area protected against the shadows. Jaheira, the High Harper and boss around these parts quickly identifies the tadpoled gang as True Souls, but after some Astral Prism action, realizes that the gang is her last hope. Either by infiltrating Moonrise Towers, posing as True Souls to learn about Balthazar and his quest of hunting a relic for Ketheric, or by learning about a "big secret in the mausoleum" from another Thorm family member, the gang makes their way to Dame Aylin, frees them, and together with the Harpers they chase Ketheric into the Mind Flayer colony.

Note: The Emperor, still posing as the Dream Visitor at this time, remarks that "oh my, how could this colony be here the whole time?" which, my god, is disconnected as hell. Why didn't he warn anyone about this for what seems to be hundreds of years? Why doesn't he later acknowledge in Act3 once he fully reveals himself that this is the very same colony he was dragged to? Why doesn't he prepare the gang for a potential face-off against the Elder Brain, something he knows that exists and is located beneath Moonrise? Absolutely useless.

On this path, Durge stumbles into a crack in the chimney wall, which causes an interaction between him and the Brain, who then promptly scolds the amnesiac Durge for abandoning it, and that he is a disgraced master (and later in Act3 claims that Durge became a pawn in the Grand Design once he was infected with a tadpole). I guess the Brain just decided that the Durge isn't worth over a betrayal that wasn't even entirely successful, and especially if the Durge would have taken an evil playthrough up until this point, doesn't even consider re-teaming. Anyways, the gang here fully learns of the Absolute plot, watch in horror as Grand Duke Ravengard is tadpoled (who is to be used by Gortash to make himself a High Duke), Orin and Gortash leave with the Brain and the army to march to Baldur's Gate, and leave Ketheric behind to collect the Astral Prism - which they later admit as a big mistake born from overconfidence (which is rather silly given Gortash is supposed to be a very, very smart person) - and then kill Ketheric and collect his Netherstone. (Note: Ketheric and Balthazar both never once recognize Durge as Durge despite both having worked with him - looks like the Myrkulite leadership aren't the only ones suffering from amnesia in this story.)

At this point, it's clear in the gang's mind that they are the only one who have the power to combat the now Dead Two and the Elder Brain. Gortash and Orin quickly begin turning against each other despite the severity of the situation, as the Brain is now breaking free thanks to losing the control of a single Netherstone. On the road towards Baldur's Gate, after one such "brain wave", the Emperor also happens to be fighting the Honor Guard and can't multitask, so he asks the gang to enter the portal and help him, where he is forced to reveal his true identity. The gang has no choice but to trust him, and gives them the option to indulge in partial ceremorphosis. Either way, Durge makes their way to Gortash first (and on the way there learns to his horror that he's a Bhaalspawn, something that is barely relevant in Act3 really), who delightfully welcomes his old friend, and the two have a lovely chat about the past, present and future. His deal is to have Durge kill Orin and retrieve the Netherstone so they can wrestle back control. Orin also makes her entrance by kidnapping someone from Durge's camp, and her deal is that "Papa wants to see us fight a duel in front of him, go and kill Gortash and let's see which one of us is fit to be Chosen and the person who dominates the Brain".

Whatever route you take, the Durge ends up being brutally murdered by Bhaal, and ressurected by Withers, something that none of your companions really care about. I guess Bhaal wouldn't want to salvage whatever He can out of Durge, as He could very much continue bombarding him with nightmares and intrusive thoughts, until eventually he establishes total mind control atop the Netherbrain and win the game (which, as a sidenote: if you side with Bhaal but defy him atop the Netherbrain, and on the docks decide that "yeah the brain was ez surely bhaal is too" Durge just gets mind controlled like, four seconds afterwards. It's not clear why Bhaal wouldn't do this at like, any point - there is nothing that would imply that something is stopping him from doing so whenever he desires, including any potentional interference by the tadpole. In fact, now that I think about it, that would make a great twist of events if the Brain wasn't so crazy - a tadpoled Durge is saved from Bhaal's control, allowing the Bhaalspawn and Brain to team up to defeat Bhaal, giving Durge the opportunity to rise as the new God of Murder, but whatever. Also, why not move the ressurection scene to the docks if you defy Bhaal in both cases and choose to commit suicide on the docks?)

Anyways, Durge tries to dominate the Brain, but all that Netherese magic building up evolved it into a Netherbrain, which basically makes the Nethershards useless unless wielded by a Mind Flayer (I guess). Either the Emperor, or a Durge who willingly becomes a Mind Flayer to undertake this task, eats the brain of Orpheus to learn to defend themselves against hivemind comms (which was completely unnecessary, but we don't care about side quests here), fights their way atop the Netherbrain which was now assaulting Baldur's Gate, defeats it, and they destroy the brain. Then the docks scenes happen and I forget to write an epilogue for this post because Larian forgot to do so in game as well.

The timeline also annoys me a lot, as many things DO NOT MAKE SENSE. Here are my attempts to piece together more information based on what you've written:

In a vault in the Counting House, Gortash's personal documents explain that the Nautiloid was dispatched to the Astral Plane to seize the Prism from Vlaakith, as it was the only device that could possibly disrupt their plan. Before the prism was lost, the Githyanki were simply fighting the Cult of the Absolute. The Emperor is the Mindflayer who tadpoles the protagonists in the introductory cutscene of the game (same armor and head shape), having been sent on the Nautiloid as a thrall to seize the Astral Prism from Vlaakith, which her predecessors had used to imprison Orpheus many, many years ago. The Sharrans caught wind of the Absolute's plan and sent Shadowheart and a covert strike team to steal the Astral Prism from Vlaakith first. Somehow (and it is not explained how) between the opening cinematic and the end of the tutorial, the Emperor gets locked in the Prism, suddenly gaining free will (set free from BOTH the Brain AND the Absolute), and using his power to save the Player Character from hitting the ground during the crash. What makes the most sense now in order is that:
1. Emperor and the Nautiloid successfully stole the Prism from Vlaakith.
2. Shadowheart and the Sharrans were smuggled aboard the Nautiloid or had plane-hopping technology, and stole the Prism from Emperor.
3. Thrall Emperor caught them, and executed the Sharrans and (later) tadpoled Shadowheart.
4. Thrall Emperor continues to tadpole people as an emergency measure for human cannon fodder while being pursued by Githyanki Dragonriders. At this point he is still a thrall and is trying not to bring the Githyanki straight to the Elder Brain and the Chosen Three. If the Githyanki found the Brain while in the vicinity of the Prism, the Red Dragons would EVISCERATE the Ghaik immediately.
5. As it takes time for the Astral Prism to have effect, eventually Emperor's prolonged exposure to the Astral Prism grants him free will.
6. Lae'zel and the Player Character get tadpoled in the opening cinematic.
7. Suddenly endowed with free will, Emperor investigates the cause, the Prism. He finds a way in and stays there.
8. Dragonriders cause enough damage that you are released from the pod and the tutorial begins. Otherwise, Emperor psionically willed you to be freed from the pod.

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Additionally, the Emperor is apparently Balduran himself, not just any Baldurian Adventurer. Balduran founded the city of Baldur's Gate (though apparently other iterations of Baldur's Gate existed prior-- continuity issues from preexisting Realms lore). Balduran "founded" the city and went missing sometime in the 1000s DR, with Baldur's Gate 1-2 taking place in the late 1300s, and Baldur's Gate 3 taking place in 1492. Moonrise Towers predates Ketheric Thorm's activities, who was active 100 years before Baldur's Gate 3, as a 1993 text indicates "Naernythra Thaloudyn was the holder of the Crescentcoat office, and lived at Moonrise Towers," with no mention of Thorm. The region of Moonrise Towers was, from oldest to youngest:
1. The site of a dormant Illithid Colony that survived from the time of the Illithid Empire. It has a Nautiloid, which means it is very old as those rarely survived from the days of the Empire. It was likely not active, probably remaining dormant and biding its time for a moment to reemerge. This is why Balduran was only tadpoled when he actively sought it out during his adventures. Only the interference of the Absolute and the Dead Three caused it to become active. This particular colony, however, was probably responsible for most Illithid activity in the southwestern Sword Coast. This Mind Flayer colony could be as old as -11,000 DR, but is probably somewhat younger than that.
2. The site of an Ancient Temple for adherents of Shar. These Sharrans were able to build a giant temple, which is abnormal for this goddess. The Temple likely predates the Selunite village that was eventually built over it, but it is possible that the temple was built in secret by members of the community. I prefer the theory that the Temple predates the Selunite village, as keeping such a massive structure a secret sounds absurd.
3. A Selunite community and some Harpers and Heralds move in before the mid-1000s and construct the section of Moonrise Towers visited by Balduran. This community, based on the demographics of the Heralds' associated organizations, were mostly humans and elves. Given Ketheric Thorm is an elf, and is thus VERY long-lived to begin with, he may have been a founding member of this community as a younger man with no renown. *****(SIDENOTE: ISOBEL IS A HALF-ELF. Ketheric went into his relationship with Melodia KNOWING he was going to outlive her and probably their children, and he STILL had a tantrum when the inevitable happened. AND he held Aylin's immortality against her EVEN THOUGH HE ALSO HAD A MUCH LONGER LIFESPAN THAN HIS WIFE AND CHILDREN.)*****
4. The community develops into a full village by the mid-1300s. Sometime between 1367 and 1392, Ketheric becomes the leader of the community. Isobel is probably born in the earlier part of that time.
5. After the death of Ketheric's wife (and, later, Isobel), Ketheric revives the worship of Shar in the area, coming to some kind of arrangement with the goddess. During this time, according to the Mason's documents, Moonrise Towers underwent further construction, likely for military purposes. In the late 1300s, Ketheric builds a NEW Sharran temple (The upper level of the Grymforge) on top of the old one. Sometime in the 1400s, Ketheric initially wins the war against the Harpers and Druids (or comes very close to it), only for Orthon Yurgir and a Devil Army to ravage his forces in the final moment. Finally, the Harpers seal Ketheric in the Thorm Mausoleum in the 1400s. The Shadowcurse is released.

It is also possible, based on Ketheric's brother Malus and the existence of (elven) Thorm corpses in the Mausoleum, that the Thorms were ALWAYS Sharrans (Ketheric's ancestors being the builders of the first Sharran Temple), and Ketheric renounced his secret faith for Melodia, only to relapse into the arms of the goddess of loss when his wife died.

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The Dead Three were dead between 1358 and 1482, give or take a few years in either direction, as a result of the Time of Troubles. This means that Balthazar could only be an active Myrkulite Necromancer 10 years before Baldur's Gate 3 AT THE EARLIEST. This gives exactly 10 years AT MOST for the ENTIRE conspiracy of the Absolute to be set up. 1482 is also the year Gortash sold Karlach to Zariel. So, your timeline sounds mostly correct. In order:
1. Gortash makes a deal with Bane and befriends Durge (early 1482).
2. Gortash sells Karlach to Zariel for infernal engine purposes (mid-late 1482).
3. At some point, he discovers information about the Crown of Karsus and the Illithid Colony beneath Moonrise Towers.
4. To get someone with familiarity with Moonrise Towers, the Shadowcursed Lands, and military affairs, Gortash and Durge task the Myrkulite Necromancer Balthazar to resurrect Ketheric. He only cooperates in exchange for Isobel's resurrection. Otherwise, he was never dead and was merely sealed in the Mausoleum, agreeing to cooperate in exchange for his daughter's resurrection.
5. For added security to his part of the deal, Myrkul (through Balthazar) devises a trap for Ketheric and Balthazar to set upon Aylin so Myrkul's champion could be immortal. How an apostate Ketheric and heretic Balthazar imprisoned Aylin in Shar's portion of the Shadowfell is beyond me. The Daughter of Selune with lawful stupid Paladin-Brain was probably lured by rumors of a revived Sharran Chosen. Balthazar's Soul Cage magic probably comes straight from Myrkul himself.
6. The rest of the plan proceeds as usual.

The objective of the Dead Three was not to be worshiped or to acquire souls, as the nature of the Mind Flayers negates these benefits. Given the Dead Three are quasi-divine beings after the Second Sundering, they chose interference in the mundane over the rest of their divine powers. I believe the Dead Three were building an impossibly massive army while simultaneously draining other gods of souls and worship. The purpose of building a powerful army in the Realms while also weakening all other Gods was to recover enough artifacts and capabilities to ascend to Greater Godhood while maintaining full control over the Realms. Recall that despite Ao declaring none would ascend to Godhood without his explicit approval after the Second Sundering, Gale can still use Karsus' Artifacts to ascend. If the Absolute hit a critical mass, it would be able to plane-hop to deny the Greater Gods ANY worshipers. At the same time, the Dead Three would use Karsus' Artifacts, Illithid capabilities, and other things they found to "build" a fully Ascended God out of Karsite and Far Realm materials (and potentially materials from the future, as this Illithid being would be able to assimilate all of the remnants of the Illithid Empire as well). Given all cosmologies are threatened by the same Far Realm, it stands to reason that components of this Divine Abomination would be beyond the control of Ao. I mention Ao because he's the reason the Dead Three died in the first place, and there are few beings quite as petty as the Dead Three. They would definitely want a contingency against the guy that basically killed them last time. Once this Divine Abomination of Karsite and Far Realm essence was completed and the Greater Gods were fully weakened and unable to intervene due to the post-Sundering rules, the Absolute would simply "eat" the other Gods, probably starting with Cyric. The motivations of the Dead Three are revenge and power: Revenge against fate, and the power to control it. In light of this particular motive, Jergal probably refers to Ao when he first meets the player. If BOTH Jergal and Ao are omniscient, then they probably formed an unsteady alliance to stop the Dead Three in light of their mutual interest: Fate spinning along as it should.

Of course, one can argue that Bane just wanted to rule everything, and Bhaal just wanted to kill. But these motives do not explain Myrkul's involvement. I think it makes very little sense for these gods to take on such extraordinary risks and efforts for their own amusement, while also denying themselves worship and souls. As Withers notes, Mindflayers do not have souls, and mind-controlled worship does not endow Gods with greater powers. If Myrkul was not getting souls or worship, and cared little for tyranny or murder, then he needed an even greater motive, being the second strongest of the Dead Three (after Bane).

1. Isobel did not seem to have died a natural cause - her dog (you can find his undead form in Ketheric chambers) died with her and he said he tried to protect her. So it looks like it was murder. Isobel doesn't remember, everything was black she said. There is speculation that this might be even Shars doing (seeing that Kethering and family are/ were Selunites.

2. Not sure about the Gauntlet but the forge that is also part of the Sharran temple is very old and predating Moonrise towers. So I think the massive temple existed already underground. So either Ketheric either just build an access from the Mausoleum to the temple and/or additionally build the (or part) of the gauntlet.

3. The mindflayer in the opening doesn't look exactly like the Emperor - it has different eye colors, even the armor is (while similar with the big head piece) a little different. I don't expect them to change the trailer which is quite old but they could have changed the Emperors appearance in the game surely more easily. So no idea why they wouldn't except for the reason that he isn't the one on the ship. Especially since our character or companions never comment on him being the one. There is also two different versions of comments from the Narrator upon finding the mindflayer in act1 (in goblin camp). One saying that this is the one torturing you and one saying this mindflayer is of slighter build.... (there is a whole discussion on reddit about it too). It makes sense that the mindflayer that tadpoled us on the ship would be the Emperor, given that he looks similar (but not the same), was at the time on the ship, was meant to be the pilot of the ship (and we see him piloting), looks upon 3 dead other mindflayers on the ship while casually (not alarmed but I mean he is a mindflayer, who knows what he is thinking) floating past them.... but, it isn't 100% sure and again, still some plot holes. He might have killed the mindflayers because they recognized that he is no longer part of the hive mind and under the brains control (there is a slate on the ship talking about one that is different, maybe that means him) or he thought it would help his plan otherwise.

4. The Emperor says that he was free directly when he found the prism (not after some time). He then followed it inside and found Orpheus und learned how to control him and planned his freedom. But we don't know exactly when these things happened. On the ship is Shadowheart with the artefact and so back on the ship he was already free. Meaning he was free when he tadpoled us (if that was him). It is also interesting that the artefact is in Shadowhearts bag and she knows it is there. While the Emperor says he stole it from Vlaakith (as anyone played as Shadowheart and talked with the Emperor? Maybe there is different dialog there) Shadowheart checks her bag and finds the artefact where she remember it was stored last. It isn't clear if she stole if from Vlaakith or the Emperor but she remembers getting the artefact. As prized artefact that he was tasked to steal a mind washed/controlled Emperor wouldn't just place it back into Shadowhearts bag. It would be safely stored somewhere, maybe on his person. But he put it back for her (at least before entering it) to immediately find it and keep it with her. Because it was important to her he could trust she would keep it. So Shadowheart was important for his plan. He might have had tadpoled others that he thought were capable of fighting and therefore helping him. All of our companions aren't just commoners, we have all useful talents. It looks like he did these preparations (tadpoles possible allies, stores artefact in pod for Shadowheart to find (but then he should have done something to help her escape) and kills mindflayers that are suspicious of him) and when the Gith arrived he goes into the prism and tries to figure out how to use Orpheus. Or he already helped us not becoming thralls or falling under the few remaining mindflayer control.

5. We learn later from the brain, that the brain released the Emperor - it wasn't just proximity to the prism. It was the brains plan to get free from the control of the chosen.

6. The first time the Emperor broke free was not by himself but he got help from his friend (dragon Ansur). Omeluum was different as it was "born" with arcane powers which allowed it to break free on its own

7. I don't think it is said how Viconia /shar people got knowledge about the prism. Maybe from Shar herself? But they see Ketheric as betrayer as he worshipped Shar before and then turned away to worship Myrkul, so this might be reason alone to intervene

The mind flayer colony beneath Moonrise was simply a dormant remnant of an age long past - however, it is incredibly lucky that not a soul discovered it during the initial construction of Moonrise and it's surroundings, and incredibly silly that Emperor stumbled into it, freed himself and didn't tell a single soul for possibly hundreds of years that the mere existence of the colony might be a possible danger. If this was revealed to any Githyanki loyal to Vlaakith, this would be reason alone to declare a full scale war on a Plane that conceals Ghaik activity.

At the very least Bhaal was active again way before 1482, as the Durge was handcrafted by Him and Him alone, and Durge himself spent many, MANY years in worship of Bhaal before he met with Gortash. Just how many years is very foggy, as you get to customize everything about Durge in game, including signs of aging, but we can very easily assume at the very least 20 years, thanks to an interaction that occurs when a Heal spell is used on Durge, where a sudden memory of the Durge's childhood of playing games emerges. In this memory, it is hinted at that Durge at this time could have already been a murderer, but was yet to find their way to the Temple of Bhaal. The lowest age you can go in customizing is making your guy look somewhat like they're in their very late teens / super early 20s, however, the pre-made origin looks very mature, which is why my assumption is 20 years at the very least. When exactly Bane and Myrkul become active again, I don't know, but probably at least some years before 1482. The Temple of Bhaal was also quite active, as Orin was born and raised in there - how old she is, I have no clue of, but likely around the same age as Durge.

It seems that I got it completely wrong that it was Bane's task to Gortash to fire up the Absolute. Bane's (and the rest of the Dead Three) motivations, as you outlined, are revenge against fate and the power to control it, however it seems there was no clear way to achieve that until information about suspended ceremorphosis reached Gortash. Likely, the original idea was to start piling up Netherese artifacts to start building up a massive stockpile of weapons to use. According to the book "To Take Control" in the vault, it is said that Gortash (together with Durge) found a portfolio labelled "Accelerated Grand Design" - the very same book you can find in Gortash's chambers - which outlined the concept behind suspended ceremorphosis using an enhanced elder brain, and that this revelation sparked the idea of the Absolute plot. Meaning that Gortash wanted / needed the Crown for whatever purpose that served Bane, which then led luckily into the creation of the Absolute scheme. Why that book was there remains a mystery to me, and why Mephistopheles didn't take advantage of it is also something that I couldn't find out.

It is after this point that Gortash discovers the Emperor's true identity, likely now trying to find an elder brain to put the crown on leading him on this trail. This is confirmed by another document in the vault called "Shield Steward Interrogation Log Scroll or letter". This log outlines that Duke Stelmane was "not herself" and that she was eating the brain of an executed prisoner, and that the person being interrogated was caught snooping around by something blue and floating, "but then it was just Stelmane, smiling". Then they don't remember anything afterwards. This seems like a giant plot hole, as the Emperor mentioned Stelmane as an ally, not as an Illithid, and the genders are very clearly distinguished - Stelmane is a female, Emperor is a male, and an Illithid Stelmane would have been dubbed the "Empress". Either that, or the Emperor was masquerading as Stelmane, but this is never mentioned by anyone, so it remains ambigious at best.

Nevertheless, Gortash achieves his goal - through the Emperor, he discovers the mind flayer colony beneath Moonrise, then they get in contact with Balthazar to ressurect Ketheric, an insanely valuable asset, becomes Myrkul's Chosen in exchange for ressurecting Isobel, then Gortash reveals the Emperor for who he is, drags him to Moonrise and has Durge put the Crown on the local brain, and the Chosen of the Dead Three dominate the brain using the Netherstones, and so begins the 10 years of setting up the Absolute.

Ketheric also becomes invincible at some point during this entire plot - remember that Isobel confesses at the end of Act2 that Ketheric in 1482 claimed Dame Aylin was dead straight after Isobel was ressurected, and that Dame Aylin, when first approached by Durge in Act2 in 1492, says that she's been there for more than a hundred years, so Ketheric was definitely sealed in the Mausoleum when he was defeated as a Sharran General, which makes ressurecting him pointless, as he's very much alive - rather, this should be understood as Ketheric being released with a Myrkulite Necromancer at the helm. But at the same time, who gave Ketheric the power to imprison Dame and make himself invincible? It couldn't have been Myrkul through Balthazar, so it must have been Shar or some unknown third party. But if it was Shar, wouldn't she cut off the invincibility after Ketheric turned to Myrkul? Wouldn't Dame be insanely skeptical of a now Sharran Ketheric luring her to some unknown place? It just seems all extremely convenient. At the same time however, Dame also mentions Balthazar as being a responsible figure in her capture, which only serves to muddy the waters even more.

Sidenote: I can't be arsed to refer to the Emperor as Balduran - that might be who he is, but given that he forgets to ever mention it or use his previous identity in some manner, it just simply has no relevence to the plot. They could have made it so that the Dream Visitor IS Balduran, somebody who would be known even to a custom Tav, and especially all the Origins.

Ten years passes, Durge is dethroned by Orin, and here, the final book in Gortash's vault comes into play. In "The Astral Prism Heist" Gortash writes the following:
"... I had (a dream) about the githyanki threat to our Accelerated Grand Design, my research led me to(...) old archives left behind in Moonrise Towers(...). These records(...) mentioned a relic or artefact called the Astral Prism. (...) This artefact was reputed to be able to project a field that disrupted illithid psionics. Such an artefact would clearly be an existential threat to both our Absolute ambitions and the Grand Design. All three of the ancient sources agreed that the Astral Prism was in the hands of the girhyanki lich-queen Vlaakith. Thus was born the plan to send a tadpoled strike team in a regrown nautiloid piloted by the Emperor to steal the Astral Prism from Vlaakith."
How the Sharrans caught wind of this plan is still unclear, and why they would have needed the artifact even more so, but this book does confirm that the Brain was acting in it's own interest now that Durge disappeared. Nevertheless, the Sharrans learn of it - but first, I want to speak a little bit about the powers of the Prism first.

So, we know that the Prism houses Orpheus, the man who is capable of distrupting illithid psyonics at will. He is the one and only person who can do this. However, it is crucial to remember that this is something he does AT WILL. If we read ahead to the beginning of Act3, when the Emperor first reveals his true identity to the gang, the player can choose to turn on the Emperor straight away and kill him. Note that at this point, the gang was in the posession of the Prism for many days, if not weeks at this point, yet if they kill the Emperor, it's game over as the Brain immediately dominates the tadpoled gang. Therefore, an ambigious rule could be established that Orpheus himself radiates a passive aura of psyonic disruption, which was then sabotaged by the Emperor as he took control over Orpheus's power to use it with intent and precision. Again, this is something that is completely head-canon and never confirmed - it seems as if the plot chooses when the Prism protects someone, and when it doesn't. Likely, there is no emanating aura to begin with, and rather, Emperor is freed at the beginning of Act1 because the Brain let him go.

Either way, the timeline is still not entirely clear, as the first two events could have happened in either order.
1: Either the Sharrans snuck aboard the Nautiloid and were then apprehended by Thrall Emperor, then Emperor proceeded to steal the Astral Prism (somehow, you'd think the Githyanki wouldn't let any Ghaik steal from their Queen), or;
2: Thrall Emperor stole the Prism, went back to Faerun where the Sharrans snuck aboard and were then apprehended.
Unfortunately, the timeline of these events matter, as Shadowheart posesses the Prism once the game begins - Shadowheart would have had to posess the Prism and then get KO-d, put in a Pod and tadpoled to excuse the fact that Thrall Emperor didn't loot the Prism off of her (again, it's a bit ambigious if the Prism was planted on Shadowheart or not). Nevertheless, it follows as:
3: Trailer begins, Thrall Emperor tadpoles Lae'zel and Durge and floats past a Mind Flayer corpse that was likely killed by the boarding Sharrans. Why exactly there are Githyanki on board is not clear, likely they were victims of the heist but this is never confirmed as far as I know.
4: Drive-by over Baldur's Gate to farm up some more people to tadpole, but the Githyanki catch up with the Nautiloid, hellbent on regaining, or at the very least destroying the Prism.
5: Thrall Emperor attempts to make an escape through some planes, ending up in Avernus, but the Githyanki are still following him. Lae'zel stumbles out of the damaged pod and begins making her escape.
6: Trailer over, Durge gets out of his pod, and Emperor breaks free of the hivemind off-screen. Frankly, it is impossible that he was freed because of the Prism as other Mind Flayers would have begun breaking free as well - instead, it is much more likely that the Brain let the Emperor go as he stumbled onto the Prism again, making it seem as if it's the Prism that broke him free. To show his exceptional lack of critical thinking, he houses himself in the Prism but fails to free Shadowheart from her Pod, but at least he finds out about Orpheus in there and begins extending Orpheus's power outside the Prism, but also finds out that Orpheus's Honor Guard is locked in there, locking him in a two-fold struggle that he struggles to multitask at. Note that Emperor does have a significant task force of Intellect Devourers inside the Prism with him - he likely brought them along into the Prism from the Nautiloid, but the why of it is never confirmed.
7: Transponder nerves are connected by Durge (who might or might not have Shadowheart in his party), the ship returns to Faerun - conveniently far away from Moonrise Towers, and conveniently the remaining Githyanki no longer give pursuit. Durge and others fall off the ship, and are saved by the Emperor - why specifically Durge and other origins is not understood, it is never hinted that Emperor tried to save anyone else.
8: Also, Emperor is a bit of an arsehole. He waits until the origins start to exhibit symptoms of natural ceremorphosis before he intervenes as the Dream Guardian, but at the same time it is also acknowledged that these tadpoles are special in the fact that ceremorphosis seems to be paused, not just by Emperor, but Lae'zel as well.

1: Ultimately, Isobel would have died way before Ketheric anyways, all this does is accelerate the plot, which it really doesn't have to - but if the theory of the murder being Shar's doing is true, then at least that makes Shar's character stronger.

2: Grymforge was built by Ketheric, everything else was before him by a Sharran community.

3: The Mind Flayer in the cinematic IS the Emperor. This is confirmed by Gortash's personal journal (in the Counting House, High Security Vault N6), in a book titled "The Astral Prism Heist".

4-5-7: These I wrote a lot about in my reply above, so I'd prefer not to repeat myself.

6: I've actually haven't fully completed The Blade of Frontiers, as I've severely sequence broke Wyll in my many playthroughs and ultimately couldn't be arsed to complete him, lol. So this information was unknown to me - thank you for revealing it. Nevertheless, it produces a new problem: there is a new entity that can block out hivemind comms at will, so how exactly does one learn to do this at will? Same deal for Omeluum - not to mention how big of an asshole he is as well that he never revealed whatever colony he came from.

I think, generally speaking, the Ketheric timeline is just broken. Due to the Troubles, Ketheric’s defeat, and the consequences of apostasy, Aylin simply could not have been imprisoned in the Shadowfell by a Myrkulite necromancer for 100 years. How could Myrkul instruct Balthazar if he was dead during that time? How could Ketheric lose if he was truly immortal, and why does Jaheira say he only returned as immortal a century later? Finally, if Aylin was imprisoned before Ketheric became immortal, why would Shar allow Ketheric to engage in such apostasy with Myrkul? How could Aylin be “tortured” for 100 years if the Soul Cage MUST post-date Ketheric’s defeat and the Shadowcurse?

Concerning Durge and Bhaal, Larian is screwing around with the pre-established timeline. Bhaal definitely died during the Troubles in the 1300s, having had many children before his death to ensure his return. One of these children was Gorion’s Ward. While Larian successfully retconned Abdul Adrian, it seems pretty immutable that Bhaal only returns after the death of Gorion’s Ward, which, canonically speaking, is 1482. It’s possible that Larian retconned the return of the Dead Three to 1462 instead of 1482, but this requires Gorion’s Ward to have died 20 years earlier. My overall point here is that Larian is making changes to the canon timeline, but it simply must be the case that the return of Bhaal only occurs after the death of Gorion’s Ward.

I think the reason no one before the Dead Three undertook the Accelerated Grand Design is that, as Jergal points out, the plan is stupid. Bane, Bhaal, and Myrkul are known for being crafty, cunning, and manipulative, but their plans often blow up in their faces because they are arrogant, shortsighted, and recklessly foolish. Myrkul and Bane were the ones who started the Troubles in the first place when they tried to steal the Tablets of Fate from Ao. Jergal notes that the other Gods (and devils!) definitely noticed the disappearance of souls and worship, and even after the Second Sundering, would find ways to intervene. Mystra, Shar, Selune, and Jergal should not be allowed to intervene by Second Sundering rules, yet clearly they find a way due to the dire nature of the situation. Jergal especially rarely intervenes in anything overtly for any reason, yet he springs into action immediately; screwing with souls and the nature of the universe and fate PISSED HIM OFF. Mephistopheles, evil though he may be, is still a lawful sort who would not take such revolutionary risks.

The Revenge Against Fate motive is more a theory of mine than something directly confirmed. The Dead Three don’t need to rule the world (except Bane), and already gave up a large part of their divine powers during the Sundering. I reason they want that power back. Given Bane and Myrkul tried to steal the Tablets of Fate from Ao already, and that Ao turned all gods mortal as punishment, I think it makes sense for the Three to want revenge and a path to greater divinity. Illithid and extraplanar capabilities combined with Karsite machinations are the closest approximation to something that can be assembled outside of Overgod control while still remaining in Realmspace.

The Artifact timeline is pretty broken still. It is not clear how it goes from Vlaakith to Emperor to Shadowheart to Emperor to Shadowheart. Clearly the following needs to happen:
1. Emperor steals it from Vlaakith.
2. Shadowheart steals it from Emperor.
3. Emperor steals it from Shadowheart and finds a way inside.
4. Shadowheart somehow gets it back while Emperor is inside and Shadowheart is imprisoned.

Alternatively, the Emperor is the Mindflayer with which the PC locks eyes before being taken out by a brick. Which makes the timeline:
1. Emperor steal Artifact from Vlaakith, is freed but hides this fact as the party can to other True Souls.
2. Emperor tadpoles everyone and plants Artifact on Shadowheart Whom he caught trying to steal it.
3. While the Nautiloid is crashing, Emperor goes into the Artifact and saves everyone.

Concerning Omeluum: I think it is established lore that some Mindflayers are born with arcane abilities from the Weave, and that most colonies kill them on sight. The reason is that a Mindflayer’s meddling with the Weave disrupts that specific Mindflayers domination by the Hive Mind. This is how we get Alhoons and Illithiliches.

I think that Kethric didn't start using Aylin for immortality until after his resurection. Before that, he captured her in the Shadowfell and kept her imprisoned just out of spite, using the dark justiciar initiation as a way to torture her. Balthazar and the soul cage came into the picture when he was returned to life. The fact he had Aylin as a resource for the soul cage just turned out to be a bit of good fortune, after a fashion.

Was it not Balthazar who betrayed Ketheric by striking a deal to summon Yurgir? Why would he do that 100 years ago if Myrkul was dead, only to turn to Myrkul about 80 years later when the opportunity arose? Aylin says she was trapped by Ketheric and Balthazar, but Balthazar is not a Sharran. Does she mean that Ketheric trapped her first in the Shadowfell, and Balthazar later with the Soul Cage? What was Balthazar's pre-Myrkul objective?

1. True, she would have died before him but this was before her natural time to die and additionally to that, I suppose that normal resurrection failed. He surely was wealthy and influential enough to get a scroll of resurrection or a high ranking cleric to help with this but he wasn't able to resurrect Isobel or he would have. Only Myrkul could do that (could Shar prevent normal resurrection but not by Myrkul?). Might explain why he was so mad at all the gods - Selune didn't help, Shar was meant to take his mourning away but it seems that didn't work too well as he still longed to get Isobel resurrected.

2. Don't you mean the gauntlet? I don't think Ketheric build the grymforge or even knew about it. This should be ancient. The gauntlet could be newer, at least there was an entry from the Thorm Mausoleum to it and it lead the way to the Shadowfell and Nightsong, which was used for Sharrans to become Dark Justiciars by killing her

3. That is the thing - we don't know for 100%. We know the Emperor was on the ship (among other mindflayers, intellect devourers and a tadpoled strike team) but the one in the cinematic does NOT look 100% the same what you noticed too. And we don't have any reaction from Tav/companions/Emperor that he is the one who tadpoled them, which is very strange. Why didn't make Larian make the Emperor model look the same and add at least one dialog line about him being the one that tadpoled Tav/companions? So - yes it is very likely that he is the one but it isn't so clear as you wrote it.

Sorry, but for 4-5 you weren't certain but the brain says it was his action to free the Emperor so we know this for sure and don't need to assume things. And he says he broke free the moment he found the astral prism and not sometime later. Meaning he very likely was already free at the time of the cinematic. Maybe already in the prism, if he wasn't the mindflayer in the cinematic.

We also don't know for certain who killed the other mindflayers - Sharrans or the Emperor.

No that wasn't Balthazar. There was the head of the Guild (sorry, forgot the name) in the town that striked a deal with Raphael to get the Sharrans killed. And Raphael sent Yugir. But he also betrayed Yugir because there is one Sharran/Dark Justiciar in the gauntlet that escaped him because he himself stroke a deal with Raphael and turned in all these rats. So Yugir could not kill him (the last Sharran) and therefore was trapped in the gauntlet.

The relic is very much safe and intact, with 3 of the Orbs required being in the Gauntlet, and 1 with Yurgir. Isn't it actually better for Ketheric to have those Orbs scattered all around the place so that no one can reach Aylin? Yurgir could have had his Orb for 100 years at this point. And now that I think about it, it also doesn't make too much sense to leave the Spear of Night lying around, because if an actual Sharran was to somehow successfully navigate through the Gauntlet and Yurgir and get to the Shadowfell, they'd kill Aylin, which means Ketheric loses his source of invulnerability forever - and this is something that happens, by the way. Aylin in every scenario is more beneficial alive for Ketheric, and even if she's spared and freed, she gets recaptured about 3 cutscenes later and placed in a temporary soul cage, which I guess Ketheric knew how to create? Balthazar never needed to reach Aylin because he has 10 years ago at that point - so with the clarifications by Gray Ghost, the timeline would look something like this:

-Ketheric traps Aylin in the Shadowfell but is not invincible yet, and then is promptly betrayed.
-Many years later in 1482, Ketheric is ressurected by the Myrkulite Necromancer Balthazar and tries to convince Ketheric to become the Chosen of Myrkul and to take part in the Absolute plot.
-Ketheric accepts on the only condition that his daughter is brought back as well. Isobel is ressurected, runs away, and he becomes the Chosen.
-Then they start putting in work to make the Absolute plot happen.
-At some point, Balthazar convinces Ketheric to create a Soul Cage around Aylin - they would have to physically go to Aylin and put her in the Cage.
-They collect the Four Orbs - whether they would have to go through the Gauntlet or if they would have to fight Yurgir is unknown. Shar would not open the door at will, as Ketheric has long forsaken Shar at this point.
-Now, Ketheric would want to seal away every bit of access to the Shadowfell and account for the smallest of disturbances (remember, he is a smart General person).
-Three Orbs are put back in the Gauntlet, and one ends up with Yurgir (somehow).
-The Spear of Night is never removed from it's resting place despite being the only weapon in existence that could kill Aylin, which would permanently remove Ketheric's source of invulnerability.
-In the event of Aylin breaking free and severing the invulnerability, baiting her to Moonrise Towers is the only way to have her reliably recaptured with some tentacle shenanigans.
-Ketheric can, at will, easily create another Soul Cage around Aylin, and does so in the final bossfight in Act2.

Do we know that Ketheric was resurrected? I thought that he has just been stewing in moonrise since the curse. On that point...the curse is Sharran in origin, was it put on Thorm after he renounced her? There used to be a book in the EA where Thorm was described as getting too big for his breeches, which was implied to lead to his downfall. I'm pretty sure Balthazar is referenced from before the cursed times, but it does make more sense if he's only brought on as part of the Crown gambit, explaining why Thorm now follows Myrkul.

Cawyden is correct in that the eyes of Emperor are purple, while the one in the cinematic, and this fella over here, are orange. And based on the fact that the Mind Flayer on this screenshot also has wildly different clothing compared to Emperor, I doubt Emperor had dressing in his priorities at that time, even with the inconsistency of the plot.

Honestly though? I am still willing to accept that the Mind Flayer in the cinematic IS Emperor, mainly based on the fact that Larian forgot about the fact that Emperor is quite literally Balduran, and so has Emperor by proxy - but of course, the facts don't suggest so. Therefore, we can assume that Zerubbabel's first timeline is what is correct.

Balthazar is the one who brings along the Soul Cage with him in 1482, therefore Ketheric must have died those many years ago as he couldn't have been invincible just because Aylin was trapped in the Shadowfell. And no, there is no trace of the Shadow Curse on Ketheric, and is never shown in the game or other books and notes to have ever been affected by it or gotten close to it without the proper protection. Balthazar does appear in the original downfall, but he couldn't have been following Myrkul then given Myrkul was dead at the time? We would have had to be Sharran.

As for any possible Shar intervention, She couldn't care less if Aylin is used as a source of invulnerability. If anything, it is a giant win for Her to have Aylin imprisoned and wait for a faithful Sharran to find the Spear of Night and kill Aylin for good - which is something that happens with Shadowheart.

Or is the soul cage just the immortality part if it

that was the year when Ketheric was ressurected. In truth, the Soul Cage could have been employed any time between 1482 and 1492, but I think it is safe to assume 1482. The game canonically takes place in 1492, and when you visit Aylin, she remarks that it has been a century since she's been stuck in there, therefore we can conclude that she was imprisoned by Ketheric at latest in 1392 - sometime after Isobel's death. It wouldn't be until at least 90 years that the Soul Cage is employed.