Honestly, the Ishar games are among the worst of their type (that is, Dungeon Master and its ilk). The graphics are all they've got going for them, because the gameplay is awkward, extremely limited and poorly conceived. It's certainly got nothing on Eye of the Beholder, Dungeon Master or Lands of Lore, and among first person RPGs on GoG the Might and Magic series absolutely mops the floor with Ishar, as does Realms of Arkania. Yes, the package is four games, but none of them are actually worth playing unless you've got an excessive amount of free time and have already gone through the classic CRPGs that made the genre so much fun in the first place.
I really don't mean to sound too negative here, I do appreciate that this is a good deal for people who may enjoy the series... I'm just not entirely sure who that would be. Personally, I like the sale because I wanted Robinson's Requiem (which I've heard other people have similar issues with, but at least it seems like a unique concept) but was never fully committed to getting it, and for three dollars I might as well satiate my curiosity.