Most importantly, Arx Fatalis allows an incredible amount of interaction with its subterranean environment. Just about everything you see, you can manipulate to at least a limited degree; throwing wooden items into fires, mixing herbs into magical concoctions, or grabbing leg-bones and clubbing monsters with them. (It's depressing that, a decade after Underworld, the seemingly simple design concept of a highly interactive game-world remains a rare delight instead of a commonality.)