I've seen it work on Containment before.

From what I've seen, anyone who makes this needs the 4 tanks glitches gametype from codejunkes or the Action Replay program, and then they can edit in Sav3r or some other program.
If anyone could make a downloadable gametype like this, tell me step by step, or refer to any other place that I can get this, that would be greatly appreciated. Thanks.
-QuickTactical