As it is generally agreed upon, the puzzles in the Grimrock games are more advanced and sophisticated than what we usually get in this type of games. There are puzzles involving text clues, visual clues, hidden switches, teleportation, time delay action, traps, and unlocking iron doors in each level. The designers came up with a nice variety of challenges with only limited objects and architecture. Of course, you can't compare these to top-notch puzzles in good adventure games. But in RPGs, especially an ancient genre like tile-based RPGs, these challenges are refreshing. The actual RPG elements in Grimrock are quite simplistic, however, with limited skills, spells, items, classes, everything. But for those, like me, who appreciate the simple charm of an old genre, this is not necessary a bad thing.