I thought Emperor was one of the worst written characters in the entire game, and I'm never not baffled by people feeling otherwise.

Sure, he talks a lot, but his personality is lacking, and he's very bland (as he should be, I suppose, being illithid and all), but he's such a charisma-vacuum as a result.

But as a result, I never felt the urge to trust him, I never got attached to him, and his ~betrayal~ left me utterly indifferent, aside from "what an illogical thing to do for someone who is supposedly smart?" thought that crossed my mind.

If he was truly a well written and clever villain, he'd side with heroes against Absolute, to backstab them in the end. Because him going "we need to fight Absolute" the entire game, and then suddenly going "Oh well, I will side with Absolute now, willingly giving up my freedom of choice that I oh-so-love" - that just felt silly and forced.

His main crime was that he was boring through and through, though.