I have found a quite a useful glitch! When you find the chainsaw and the revolver, set chainsaw as primary and revolver as secondary and press accept. When the screen goes black switch weapons, then when you start the horde you should have the revolver with 50 ammo! I have not tried with other weapons so you can try for yourself. It works for me, rate up if it works for you!
When you use gas like freshadow says, be careful not move your troops into a gas cloud excluding tanks, because it kills all toops, yours and the enemies. Press + if you agree with me.
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