A couple of levels, and a small shapes patch. The first level is seriously claustrophobic, and you'll be hitting your head on the stairs every time you go down. The fun part comes in with the small shapes patch...

A simple arena, in principle... but play it for a little while, and you might change your mind. The hill is accessible via 5D passageways from the outer ring... and you come out on the far side from where you started. Big weapons are on the hill, everything else is in the pit surrounding it... and to make matters a bit more complicated, 3x canisters can be found in sort of hidden corners (we found ourselves shooting at them just out of principle... you never knew when someone would be in there). Adds up to serious carnage, with anything more than 2 players.

A large arena surrounded by multilevel ledges. Lots of weapons, lots of ammo, and lots and lots of bobs... smaller groups will have trouble staying alive long enough to kill other humans, because the bobs will gang up on you. Larger groups should be okay, though...

A preview of the upcoming scenario, Hoth. This contains a single solo level and two net levels... definitely gives you a flavor of gameplay.