Lots of corridors, no places to hide, no aliens. If you use the enclosed shapes patch, the walls have pictures of all the IRC #marathon folks. Way too many invisibility powerups (IMHO).

I hate the textures, but the level's pretty fun with three players. Look for the Spanker!

Towers and elevators. Hard to see the point without someone to play it with. Comes in a normal and vacuum version.

I found it cramped. You might not, though.