An abandoned church, with a few elevators, some teleporters, and a secret passage or two. Always keep in mind-if you can see them, they can probably see you... Update adds lots of secret passageways, reworks some of the existing ones, and generally cleans up. (A much sneakier level, now...)

A multilevel arena. The textures keep you from getting your bearings for a little while... and your opponents will keep you from it for as long as you play. Very open, with lots of ways to get from point a to point b. Always check above you...

A large, rambling level, with distinctive lighting effects, and some weird spatial quirks. Plenty of ammo and weapons... so as soon as you've figured out the flow, carnage rates should be high.

A two level arena...Carnage should be high. Don't look at the ceiling-it's a bit weird. (While you're trying to figure out why it bothers you, you'll get a grenade in your back...)