I'm guilty of having an ego and I think a number of the battles are beyond what one would expect for a 'core' setting. I've played all the related games at core setting, I've DMed for 3.5 games and while I'm new to pathfinder I understand the base rules pretty well. The ACs / DCs and the like are just absurdly high for a setting that putatively reproduces a tabletop experience. The devs would do themselves a favor to rename that setting.
Still, I'm having fun with the game. It plays like a modded version of a DnD game and that's fun. But some of the battles I don't like -- I also disliked the Endless Paths dragon from PoE1 and the titan from PoE2. These bosses are built with a similar mindset.
For me the best bosses from the related games were the red dragon from BG2 and the demon doctor from DOS2. In both cases you needed to have a good understanding of the ruleset to win but the difficulty wasn't turned up to 64.
There's a three bears place with difficult battles. Those two were just right.
