Amazingly simple, but pretty convoluted... two completely overlapping rooms, with a shared pair of pillars. There's a moving platform between the pillars (you can use it as cover, or as a travel aid), and each time you circle a pillar, you end up in the other room. One room has drones, the other has a single cyborg-leave aliens on during net play, and you can use the wreckage to orient yourself. Beautifully done.