Enter "SOYINCAPAZ" as a name to enable cheat mode. Then, press one of the following keys during a game to activate the corresponding cheat function. Cheat mode can also be activated during a mission by typing "SOYINCAPAZ" after selecting a commando (you cannot see what you type and there will be no confirmation).
Result
Cheat Code
Invincibility [Ctrl] + I
Invisibility [Ctrl] + V
Destroy all opponents [Ctrl] + [Shift] + X
Mission skip [Ctrl] + [Shift] + N
Place selected commandos under the pointer [Shift] + X
Display frame rate [Ctrl] + [Minus]