X-Com: Apocalypse Cheats

Hold [Alt] and type tac cheat. The message
bar will confirm that cheat mode has been enabled. Enter one of
the following codes to activate the corresponding cheat function.

Code
Cancel cheat mode [Alt] + [Esc]
Toggle training [Alt] + T
Toggle hidden terrain [Alt] + H
Toggle hidden units [Alt] + V
Kill hostile units [Alt] + K
Toggle invincibility [Alt] + I
Toggle weightlessness [Alt] + W
Increase music intensity [Alt] + F
Decrease music intensity [Alt] + G
View FMV sequences [Alt] + U