Circle of Carnage
Pillars, lava river, lots of ways to die. There are a couple of elevated rooms off the sides, with 2x rechargers in 'em... careful, 'cause they're guardable. (Also watch for a weird bug if you leave too fast... you can end up in a glass cage at the bottom of the stairs.)
Levels in map "Circle of Carnage":
Circle Of Carnage