Arena of Doom is meant to give some new twists to standard CTF designs: The flagrooms, though they are under the standard "floor" of the level, and only have two entrances, are NOT camping grounds. If you're going to defend your flag, go on the offense. The choke points in the level are minimal, if non-existant. The worst choke point I can think of off hand is the sniper room*, which has only two entrances plus the sniper ports. The worst choke point I can think of that would actually be used in CTF is the area going past the sniper doors; there are only 4 tunnels that let you get between the level halves, all of which pass near to the sniper doors. Energy is plentiful for the tankers out there, though you might have a hard time finding a fusion cannon. There is a general sparsity of weapons; but all spawn points start close to weapons. Oh, and did I mention that the weapon spawns are hidden?
*Read the .txt file included with the level to hear about an interesting feature of the sniper room.
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