The wonderful folks at Giant Bomb got their hands on a copy of Crawl, which lets you explore a dungeon where your friends are the monsters. It looks like the game's sense of humor is already living up to its excellent trailer.
You can check out the gameplay in the video below. It's an early version of the game, so there's still a lot that can change, but it already looks like a lot of fun, even if it has a somewhat slow start for the players controlling the monsters. When a ghost player kills the human, it looks like the switch happens pretty quickly so the game keeps moving at a good pace despite constantly switching who's in control.
Crawl: Giant Bomb Unfinished [YouTube]