Octagon

The Octagon arena is an octagon-shaped arena with two hellraisers (flippers), two hammers, and four pits that will eliminate any bot that falls into them. The Octagon is probably the most diverse arena, with a variety of hazards. An interesting thing about the Octagon is you can be flung out of the arena (by one of the hellraisers or another bot) onto the the raised part of the arena, granting you pretty much total safety unless an AI bot is already up there.