Do we have a list of exactly how the difficulties will differ? I read something about +2 proficiency on easy mode, but that can't be it..?
Only in some vague terms:
Difficulty Levels & Rules
In D&D, picking the right DM is key to defining the journey you want to embark on. In Baldur’s Gate 3, we’ve created three modes of play that essentially act as different types of DM: the forgiving, narrative driven DM, or the DM that isn’t afraid to let you die if your glass-cannon wizard decides to tickle an owlbear.
At launch, in addition to ‘Normal mode’ (which can be considered our default), players may avail of the following:
In Story mode, combat has been made more forgiving so players can fully immerse themselves in the narrative layer of this adventure. In this mode, friendly NPCs are harder to kill, trader prices are at a 20 percent discount, and you'll begin the game with a +2 starting proficiency bonus.
Hardcore mode, then, is where to test your mettle. In this mode, enemy lethality is cranked up to Brutal, ensuring that enemy AI are stronger, will prioritise squishier targets with low AC, and will seize opportunities to go in for the kill. Additionally, many adjustments have been made to the fights themselves specifically for Hardcore mode, with certain enemies receiving additional support through reinforcements, spells, or consumable items.
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And to answer the thread's question I'm planning to play in Hardcore mode.
Ideally also with the six-character party mod.
But I would love to know more details about the difficulty options. I just hope they won't go and arbitrarily buff creatures in the HM because that's not just about difficulty, it alters how the game plays.