BIG SPOILERS AHEAD FOR THE EMPEROR!!!

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First, I don't think that the Emperor should be Balduran. I don't think that this adds anything to the character, and I believe it actually detracts from the "I was an adventurer, just like you" presentation that was initially given. I don't know that the Emperor delivers on feeling like someone whose footsteps the player might be following, but I do know that as soon as the Emperor is revealed to be Balduran, the identity of "founder of Baldur's Gate" completely usurps any other concept of who this character was pre-illithid, and it adds nothing. Balduran is not significant to the story of BG3, and finding out that he became an illithid after his final voyage does nothing good to Balduran's own story. I think the Emperor should simply be an unnamed adventurer whose original appearance is the one we see as the Dream Visitor.

I personally quite enjoy the reveal
that he was once Balduran.
I like that Larian fully leaned into the idea that you may not want to meet your heroes. Having him be a legendary hero actually works quite well as the player character is well on their way to becoming a legend in their own right. If he were just some adventurer whose actual appearance was that of the Dream Guardian, then the mechanic of having the player designing their Guardian wouldn’t make much sense in the story. The whole idea is that you create your Dream Guardian as a figure you would trust, which later turns out to be an Illithid who studied you and picked that form as a means of manipulating you to his cause.

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As a note, I would personally try to find some other name for this character other than the Emperor, to reflect the genderless illithid and player-designed original form of the character.

I think sticking with the name is not necessarily an indication of gender in this instance, as it seems like a name he just enjoyed. Having said that, he is heavily coded as male both before and after becoming an illithid, and given he still retains much of his humanity, I think having that coding carry over into his current form makes a lot of sense. The game seems to intentionally avoid calling him male as far as I can remember, so in some ways he does reflect the genderless illithids while also being coded male.

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The Emperor Romance
This is slightly going off-topic, but I really wish that the Emperor weren't so overtly interested in sex with the player. It feels incredibly strange coming from a mind-flayer, and this character seemed like one who'd be a good candidate for a character the player would have to be the one to express sexual interest in. There can still be a quiet scene of the Emperor expressing that they've come to enjoy the player's company and possibly even reflecting on missing their days of working with their party, but I think it should be up to the player to express romantic interest in the Emperor, which the Emperor can go along with after expressing some confusion.

Also, I feel like the ability to romance this character should probably be exclusive to the Trust path (i.e. not a player who's constantly telling the Emperor how much they hate him / mind-flayers), and some other conversation can occur here on the Distrust path -- still on the subject of companionship, but with a different tone. For example, for the Emperor to remark that he knows that neither of you are happy about the current arrangement, but trying to encourage you to stay focused on your mutual goal of beating the Netherbrain and then going your separate ways. This seems like a good way for the scene to still have the overtones of "the Emperor reaching out" while still acknowledging the distrust between the parties.

I think that a romance with The Emperor should likely be tied to a hidden approval rating, but I think it would be a mistake to tone down his sexuality. Not only is it part of his appeal, but there are clear and intentional elements of his character design that are meant to evoke a strong, male sexuality. For example: his voice, the way in which he stands with his hips cocked forward, the design of his armor with the codpiece, and the way in which he describes the beauty of being an illithid are all meant to have a strong current of sexuality that is both human and reminiscent of a male romantic archetype found in many other romances stories including monster romances. Diminishing his sexuality would be at odds with his character design. As far as it feeling weird that a mind flayed would be so overtly interested in sex, remember, we’re not talking about just any illithid here; we’re talking about The Emperor. This is an illithid who is both alien and human with both illithid and human desires. I also find that him being able to experience sexual desire and pleasure without traditional human or reproductive anatomy is important in a game that’s as inclusive and diverse as it is. I think the real issue comes down to the lead up to the romance scene not being properly established, and that throws people. (I also think a lot of people are salty about the Dream Guardian reveal, but I digress). While I understand that the romance scene follows what is, in many ways, an intimate moment for him with the player as they go through his old possessions, one way to better establish this scene would be to create a dialogue between The Emperor and the player character as they explore his personal belongings. Depending on the player’s choices during that conversation, it could lead nicely and naturally into the romance scene at the next long rest.

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Generally speaking, earning the Emperor's trust comes from dialogue choices that show an open-mind towards mindflayers, acknowledge the Emperor's desire for safety, and can appeal to logic rather than morality. Losing the Emperor's trust comes from options that resolve disputes with them via intimidation or force.
For example, when discussing the Orphic Hammer:
- Trust-path solutions might include reassuring the Emperor that the player does not see freeing Orpheus and killing the Emperor as intrinsically linked (attentive the Emperor's concerns); or pushing for the pragmatic idea that having the hammer around may be useful later and shouldn't be ignored just because it makes the Emperor nervous (logic-based)
- Distrust-path solutions would be based on simply telling the Emperor that since they're dependent on the party, they have to go along with this (intimidation); or options that involve resisting the Emperor's psychic attempts to interfere (by force)
I'd also like to note that submitting to the Emperor's demands every time a conflict arises is NOT the same as choosing the "Trust" path -- this is not about whether the Emperor likes the action you're taking, but whether you're challenging his mindset about how a party should be run. I'd probably make most options that concede to the Emperor simply be neutral; he has not changed his opinions in any way.

I think these are great, and I like how it involves not just going along with everything The Emperor says. I think part of the reason some people have strong negative feelings about this character is that you can’t influence him in the way you can other characters, and maintaining a good relationship involves following along too much for people’s liking. Having said that, you can definitely not take the astral tadpole and have a good relationship with him, but more options would make the relationship feel more equal.

As far as your suggestion that the player make skill checks to avoid The Emperor’s manipulations, this creates too many problems with his character development. I’ve written in another post about why I think he never enthralls the player character, and regardless of whether that’s the actual reason, one thing that sets The Emperor apart from other illithids, or at least our expectations of them, is that he never controls the character in that manner. He seems to genuinely value their free will.

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When you catch up to him in the Astral Prism, the Emperor is clearly in a hard-pressed fight, but he's not on the ground. Perhaps you even see a glimpse of him in Dream Visitor form before having the illusion broken, due to the effort of fighting.
Upon seeing you, his reaction is along the lines of "Finally! Now help me defeat these enemies!"
Based on my personaly experience in this encounter, I think the reaction of the majority of players is neither to immediately attack the Emperor, nor to immediately assist him, but instead more like "WTF is going on here?!" And this is where I think the major shift should be.
The Emperor has no patience for your questions right now. I'd give the player perhaps one simple question they can ask ("Dream Visitor, is that you???" / "Yes! I'll explain later, now fight!"), and if the player hesitates any longer than that the Emperor will mind-control your entire party and use them to finish the fight.

The same problem occurs here as far as his character. The Emperor, as he is now written, seems to value the player character’s free will and agency and any threats he makes to the contrary are toothless and all bluster. Changing this not only undermines what is unique about him as an illithid, but he is just, frankly, a different character entirely at this point. I think a little awkwardness in the fight is worth keeping this fundamental aspect of his character intact.

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The Emperor's Character Arc: The Trust / Distrust Path

Now we're getting into the idea I put forward in the earlier Emps and Orphs thread. Mainly, the Emperor's arc hinges on the idea of whether they trust the party (and respect the party's decision-making) or whether they distrust the party (and are inclined to try to manipulate and assert control over them). Our themes here are basically trust, control, and leadership, which I believe fit with the narrative the game has presented.

As a general background for this section, I found that one of the most compelling interactions I had regarding the Emperor was during Jaheira's quest to rescue Minsc. Jaheira wanted to save Minsc by knocking him out, and I put in the effort to make sure to keep him alive. But the Emperor nearly refused to extend the Astral Prism's protection to Minsc, requiring multiple rounds of advocating for it by both the player character and Jaheira threatening to throw the Emperor into a volcano. And the fact that there was an actual possibility of not persuading him here (by choosing to concede) made it one of the few times that it felt like the Emperor's threats had any teeth to it (I'll talk about this more re:Orphic Hammer). I'd like to see more interactions like that, though not always as extreme.

Throughout the game, I would have the Emperor do a mix of two things:
1) Advise the player on how to run their party and discussing the subject with them
2) Meddle with the party's course of action, effectively challenging the player's control of their party

The intent here is not quite to actually be a serious threat to the player's choices, but to give the illusion of a threat, and to make the METHOD of exerting control over your own party be an important part of the Trust/Distrust dichotomy. The debate with the Emperor is essentially that of how to lead and direct your party -- the Emperor advocates for manipulation and overriding the agency of others, while you can choose to advocate for diplomacy, respect, and compassion; but how you treat the Emperor is an important part of that, as well -- you don't get to try to preach about listening to others but then constantly take the Intimidation path with the Emperor himself without it leading to a fight later on. Where the Emperor falls on the Trust / Distrust spectrum is the product of the player's own "leadership style" -- either a hard-earned ally, or an enemy of their own making.

Generally speaking, earning the Emperor's trust comes from dialogue choices that show an open-mind towards mindflayers, acknowledge the Emperor's desire for safety, and can appeal to logic rather than morality. Losing the Emperor's trust comes from options that resolve disputes with them via intimidation or force.
For example, when discussing the Orphic Hammer:
- Trust-path solutions might include reassuring the Emperor that the player does not see freeing Orpheus and killing the Emperor as intrinsically linked (attentive the Emperor's concerns); or pushing for the pragmatic idea that having the hammer around may be useful later and shouldn't be ignored just because it makes the Emperor nervous (logic-based)
- Distrust-path solutions would be based on simply telling the Emperor that since they're dependent on the party, they have to go along with this (intimidation); or options that involve resisting the Emperor's psychic attempts to interfere (by force)
I'd also like to note that submitting to the Emperor's demands every time a conflict arises is NOT the same as choosing the "Trust" path -- this is not about whether the Emperor likes the action you're taking, but whether you're challenging his mindset about how a party should be run. I'd probably make most options that concede to the Emperor simply be neutral; he has not changed his opinions in any way.

While I don't know the exact mechanics of what's going on in the Astral Prism, I am going to say that the Emperor can exert their own psychic influence over anyone in the range of their protection, meaning that they can meddle with nearby NPCs, although they are subject to the party carrying them around. This is to give them some ability to back up their threats, as well as possibly offering some tangible assistance in certain scenarios. In most cases where the Emperor is going to interfere, I would attach a short dialogue with them (as seen in the case where they talk to you after Raphael proposes his deal) that can either persuade them not to interfere (or to be helpful), or call them out on having done so.
For examples of behavior they might demonstrate:
- Manipulating NPCs to avoid answering certain questions, such as if the player tries to talk about the Astral Prism or Dream Visitor to NPCs who have no business knowing (for example, trying to bring it up to druids at the grove, anyone at the goblin camp, etc). These might be unavoidable, but the player has the chance to yell at the Dream Visitor over it
- Alternatively, forcing the player to make saving throws in order to speak of certain things, like when telling the githyanki about having the astral prism (these can be the weak DC 5 checks; the point is just to create the feeling of interference)
- Manipulating the actions of anyone in their range, and not just those branded by the Absolute. This can be a chance for the Dream Visitor to show their support of certain courses of actions by manipulating guards, etc. to allow the players to proceed more easily.
- Threatening to expel companions from their protection

Act 1 -- Opinions and Advice
Although the Emperor may not be willing to break with the party over their decisions, they should still have more opinions about how the party decides to resolve various quests, and rather than just saying lines that the player can't respond to, I would like to see some actual discussions here.
The pattern I would like is for the Emperor to talk to the player before a major decision is made, both offering the Emperor's preferred path and then asking the player to state their intended path. The Emperor need not interfere just because they disagree, especially early on. But then after the decision is made, I would also like to see the Emperor comment on whether the player did as they said they would do, and whether they stand by that decision. And I see no reason to have the awkward delay waiting for long rest dream sequences with the character for all of these; they clearly demonstrate the ability to communicate telepathically whenever they please in later acts.
For example, if a player chose to defend the Grove and had said they were interested in protecting people, the Emperor may comment on how many goblins had to be killed in that fight, and whether this bothers the player.
The companion quests may also be the subject of conversation -- particular in Act 1, I think the Emperor could comment to the player character about the company they keep, rather than talking to any of the companions directly (saving that for later). The Emperor should voice their suspicions about every party member, generally warning the player to watch their back and make sure to keep everyone in line, and other advice one might imagine a manipulative sociopath giving when it comes to controlling their minions. Effectively, the Emperor is trying to use the player as their proxy, since they cannot lead the party themselves (they may even cite anecdotes from their former adventuring party as part of their advice). Not all of their commentary needs to be wrong -- particularly when it comes to knowing each companion's motivations and insecurities, I would expect the mindflayer to be spot on, just in an exploitative way.

Act 2 -- Tempting the Party Members
Playing off the way the Dream Visitor is presented as trying to tempt us to take power, I think I'd like to see cases of the Emperor talking to other companions and providing discussions and debates for the player to weigh in on (loosely echoing some of the intentions with Daisy, I think). I think Act 2 would be a prime location for some of these, as the story otherwise feels a bit narrow, and the feeling of one of your main conversation partners being the voice in your head would fit nicely with that while still fleshing things out a bit more. I would aim for the Emperor to encourage the "ascension" path when available, but keeping the Emperor's own personal interests in mind, too. Some ideas:
- After Gale receives the visit from Elminster, Gale can be seen talking to the Emperor. The Emperor is discussing Netherese magic with him and suggesting the idea that perhaps there are other ways to harness the orb's power other than simply blowing up (with hints towards Gale potentially taking the crown later)
- The Emperor may encourage the player character to help Astarion ascend, as a Vampire Ascendant would be a useful pawn against the elder brain (Astarion currently comes up with this notion himself, but I wouldn't mind some tweaking so that the Emperor is the one who suggests it, and for Astarion to be a little hesitant but very tempted by the idea)
- The Emperor may be in favor of Wyll maintaining his pact to secure the power he has from Mizora (or if the timing were slightly different, to become a political challenger to Gortash)
-The Emperor may try to dissuade Lae'zel from looking for Orpheus, perhaps trying to convince her that this is all a trap set by Vlaakith to lure dissenters into chasing for a dead prince. This may even spark a little quest to find some proof that Orpheus is alive, like encountering a member of his honor guard who's looking for help (and for the Emperor to try to convince the party that this is a spy sent by Vlaakith).
- The Emperor may talk to Shadowheart about her missing memories, offering to unlock some of them, in the interest of trying to pry into her quest (maybe replacing the Noblestalk interaction)

Act 3 -- Start
To kick things off, I would tweak the first major encounter with the Emperor slightly.

Currently, when we arrive in the Astral Prism and see the fight, the Emperor is on the ground, begging us not to kill him, and trying to persuade us that he is our protector. We then have a frankly puzzling amount of time to sit there questioning him, which he patiently endures, WHILE THE FIGHT IS STILL HAPPENING. This, I think, is a horribly missed opportunity for a far more interesting introduction to this character, one which could do a much better job of creating tension between the player and the Emperor (for both those who want to befriend the character and those that want to kill him), as well as one that just... doesn't involve a weird pause in what is supposed to be an active fight.

When you catch up to him in the Astral Prism, the Emperor is clearly in a hard-pressed fight, but he's not on the ground. Perhaps you even see a glimpse of him in Dream Visitor form before having the illusion broken, due to the effort of fighting.
Upon seeing you, his reaction is along the lines of "Finally! Now help me defeat these enemies!"
Based on my personaly experience in this encounter, I think the reaction of the majority of players is neither to immediately attack the Emperor, nor to immediately assist him, but instead more like "WTF is going on here?!" And this is where I think the major shift should be.
The Emperor has no patience for your questions right now. I'd give the player perhaps one simple question they can ask ("Dream Visitor, is that you???" / "Yes! I'll explain later, now fight!"), and if the player hesitates any longer than that the Emperor will mind-control your entire party and use them to finish the fight.
Now, you may protest that this is a horrible breach of player agency in this scene, but... the game is going to railroad you into working with the Emperor regardless. Why not use this as an opportunity to establish the Emperor's "villainous" side and his willingness to do whatever it takes to ensure his own survival? Far more fitting for the character than simply begging for his life, I think.
After the fight is finished, the Emperor will then release his control over your party, and he will now act a bit conciliatory. He'll cite to the urgency of the crisis as his reason for acting as he did, and he will now be ready to hear out your questions and concerns in a calm manner -- this behavior is not to be mistaken for saying that the Emperor is really a good person, but rather showing how much he values being "in control" of the situation; he'll entertain your questions only when he's certain of his own safety.
Here, players who really want to attack the Emperor will get another chance to. This time, the Emperor is a bit tired from the previous attempt to mind control you (he cannot maintin this long-term), but he will try again. He'll make all the arguments he can about how Orpheus will not protect you, as well as just pleading with you to cooperate willingly. If you continue to refuse, you'll get the game-over. It can be open to interpretation whether he broke your mind a la Stelmane, or if all of you were overwhelmed by the Absolute in the chaos. This shift is designed to point the player's frustration where it belongs -- not at Orpheus for not protecting you, but at the Emperor, the character you've actually been interacting with throughout the game. No one who takes this route is going to be happy about "being forced to submit," but that frustration will later be vindicated in the boss fight with the Emperor, assuming that they stick to the Distrust path; that's the real point here.
Otherwise, I think the common path will be that players will first hesitate, and then hear the Emperor out, and then be very uneasy about the whole situation without quite knowing how to act yet. They do need the Emperor's protection, after all, but they'll probably want to get away from this guy once the opportunity presents itself.
Basically, this whole encounter is designed to demonstrate that the Emperor is clearly willing to usurp control of your party from you and use you as his pawns, but he doesn't necessarily mean your party any harm -- at least not while you all have an enemy in common. I believe that is the correct effect to aim for (based on how characters talk about the situation).

Act 3 -- Clashing with the Party
I'd look for some opportunities for the party members to now be in heated arguments with the Emperor for various reasons, some of which could result in the Emperor threatening to expel the party member from their protection if they don't comply. For some alternatives, the party could be trying to convince the Emperor to assist with their own plans and be annoyed that he isn't cooperative (for those who aren't as inclined to be hostile towards him). These could be tied to their personal quests or alluding to the party's offscreen attempts to further the main quests.
Some examples:
- Lae'zel trying to develop a way to open the astral prism by force and angering the Emperor
- Wyll commenting that he was trying to gather information in the city, and the Emperor interfered by manipulating NPCs to hide information (alluding to Stelmane / the Emperor covering his own tracks)
- Astarion trying to get the Emperor to mind-control some people for him to help him find more information about what Cazador's been doing (or trying to learn how to take control of the ritual)
What stance the Emperor is taking on their personal quests / what they're arguing over will have to be reconciled with whatever the Emperor is encouraging them to do in Act 2; it obviously wouldn't make sense for him to interfere with doing the exact thing he was suggesting that they do. These are just loose ideas.

Act 3 -- Orphic Hammer Questline
This was the questline where I had the most specific ideas for ways the Emperor could meddle with you, for obvious reasons. It's the one he has the most personal stake in and the clearest stances on. If the Stelmane quest were more central, I'd say that would be a prime spot to focus on, as well.
My experience with this quest was that the first time I did it, I did not take Raphael's deal but stole the hammer later. The Emperor confronted me about it, and I was curious how harshly he might respond, but my character had expressed an almost naive level of "It's not right to keep Orpheus imprisoned, but I don't actually have a plan," and the Emperor laughed it off, which seemed fair enough.
In my second playthrough, though, I wanted to test some of the dialogue options a little more. I took Raphael's deal (which seems like a terrible idea, frankly), then attempted to lie to the Emperor about it, failed at hiding it from him, and then braced myself to see what the Emperor would now do.
Nothing. He did nothing. Because he can't. He has nothing he can do to back up his threats against us. This is one of the main reasons I just cannot get behind the feeling that he's such a threatening villain. He complains, but he can't hurt us.
Here's my idea for how this quest line plays out:
- The Emperor, as he does now, tries to find out what Raphael offered the players. If they refuse, things can stay basically the same. If they accept, the Emperor will act oddly calm. He'll be very disapproving, but he makes no comment about his future courses of action.
- Let's say the party refused the deal (because this is the one I'm familiar with). They'll then try to go to the House of Hope to steal the hammer. If the Emperor knows what the deal that was offered was, then he can put two and two together and knows what the player is intending to do in the Hells. Before opening the portal, this sparks a dialogue with the Emperor. The player can try to convince the Emperor to allow them to take the hammer, for various reasons. If they succeed, he'll back off. If they fail, then they have to make a saving throw against the Emperor; if they fail the saving throw, he briefly mind-controls them and destroys the ritual components, preventing them from opening the portal (but they can still go accept Raphael's deal if they really want the hammer).
- If the Emperor did not know about the deal before the players entered the House of Hope, he comments on them having the hammer upon their return. Again, there's a chance to converse with him and attempt to convince him to go along with this. If they fail, he simply expresses disapproval.
- If the Emperor is still not convinced, then on a later long rest, the player wakes to find Lae'zel (if available) wrestling with an NPC who's trying to make off with the hammer. The NPC is a random people who's being mind-controlled by the Emperor in an attempt to hide / throw away the hammer so that the party cannot use it. There's one final chance to potentially debate with him about it, although no matter what, the Emperor is forced to yield here -- the hammer is too secure for him to get rid of it.
- For one option on the Trust path, at any point during the conversations with the Emperor about the hammer, the player can offer to let the Emperor be the one to keep the hammer, telling him it's just in case of emergencies down the line. This will make things a little harder if the player later ends up fighting him, but it'll be an easier way to get the path to convince the Emperor and Orpheus to work together.

Also, throughout this process, the Emperor's behavior should be influenced by where he currently stands on the Trust/Distrust (Approval) meter, and perhaps whether his personal quest has been resolved. If the Emperor has already been pushed heavily towards the side of Trust, then he should stop being so inclined to meddle. The DC of the various skill checks against him can also be adjusted based on where he currently stands, making it easier to talk him down the more often you take the diplomatic approach.

Unfortunately, I think many of these proposed changes compound the problem of The Emperor being multiple things at once and fundamentally change him in a way that lessens the character. Why would any player pursue a friendly alliance or romance with him if he blatantly meddles in your leadership, threatens your companions with expulsion, psychically manipulates you, frequently encourages you to mind control others, and takes away your free will and agency when it’s convenient for him? He goes from an antihero to a sociopath at that point. What’s unique about The Emperor is how he subverts our expectations. Yes, he’s manipulative, but he never mind controls you. He’s this supposedly asexual creature, yet he’s sexually interested in the player character and is heavily coded as a romantic male lead. He’s also supposed to be this heartless and soulless creature, but expresses care for the player character, and if you romance him, he’s sweet, vulnerable, and sincere. He’s supposed to be part of this hive mind, yet he wants his freedom and actively encourages the player character to form alliances to defeat the netherbrain. He needs to feed off the brains of others, but avoids the innocent. He may want the player character to change into an illithid, but he leaves that choice entirely to you. He’s alien, yet very human and desires allies and companionship.

If Larian fleshed out his personal quest involving
Stelmane, this would go a long way in resolving some of the issues around his character. I’ve talked in another post about what I believe happened between him and Stelmane, link here, and to summarize: I believe they had an alliance but that alliance fractured badly, and acting out of self-preservation, he attempted to control her or pull information from her mind and unintentionally disabled her. I believe he feels remorse and grieves the loss of their relationship, and I believe that explains a number of things the game presents to us. If Larian were to flesh out his personal quest involving Stelmane in a way that provided us the backstory of their relationship, The Emperor’s role in her illness, and how it affected him while not absolving him of his actions, that provides all the groundwork required for a more meaningful choice as to whether or not to ally with The Emperor, continue to romance him if you already are, or to become his enemy.
As long as the backstory to this has room for him to show his humanity and growth, then the player can decide what impact that has on their relationship for better or worse, without adding all these elements that fundamentally change his character. If Larian were to add dialogue options with The Guardian and Emperor, especially when they interact with the player from the astral prism, those dialogue options could lead down either antagonistic or trusting paths that build the relationship in meaningful ways. All this can be accomplished while still maintaining his character as someone who respects your leadership, your free will, and desires your alliance, if not your companionship.

I would personally like to see the romantic or ally path resulting in the possibility of having The Emperor and Orpheus work together, while an antagonistic path wouldn’t provide that option. I think that resolves much of the issues with the ending while still allowing consequences for the player’s actions, and to allow him to fill a proper villain role in the end as part of the boss fight.

I hope that if Larian were to add additional writing and development for The Emperor, that they wouldn’t fundamentally change his character. What’s so great about him are the fundamentals of his character. Where things falter, largely comes down to elements of the execution.