A huge, rambling level. There are a few funky textures, and it's really easy to get lost, but with a big enough group, there should be something for everyone. One thing's for sure-you'll never, ever, run out of ammo.
A small arena with a sewage-filled pit in the center (hence the name), but most of the action seems to congregate in the side passages, where the weapons are... Drop back into the pit for ammo and a recharge canister. Keep an eye out for secret passages...
What it sounds like. An open arena with a raised cross in the center. Ammo and shotguns on the main floor, assault rifle one level up, all the big guns are a little harder to get to... See what you can do about getting the flamethrower with someone on your tail.