I believe there are various artists. Checking out the credits from the players guide it says... Art Direction: Gaear Graphics and Eye-Candy: Cujo, Half-Knight, Vampiric Puppy Maps: Screeg, Vampiric Puppy, Ax Thrower, Krunch, Allanon, Big Little Boy, Gaear Worldmap: Sherriff05
Yeah, a lot of effort went into the art by a lot of people. As well as those mentioned, you have guys like Ioannis and Maggit who did other artwork such as inventory icons and portraits, and all the other portrait makers (albeit Half-Knight and Daadamo did the majority). Re the Keep, essentially, Geear did an overhaul of the Main Gate and Outer Bailey, while Screeg did the pre-overhauled versions, and Screeg did every other map in the Keep area (including the graveyard) and the Thorp.
