Cheatcodes:
ALIAH -- Change between imortality and normal gameplay.
FATAL -- All weapons and ammo.
Level codes:
LAVA2 -- Mission 1 stage 2
LAVA3 -- Mission 1 stage 3
GATE1 -- Mission 2 stage 1
GATE2 -- Mission 2 stage 2
GATE3 -- Mission 2 stage 3
CROC1 -- Mission 3 stage 1
CROC2 -- Mission 3 stage 2
CROC3 -- Mission 3 stage 3
HEAT1 -- Mission 4 stage 1
HEAT2 -- Mission 4 stage 2
HEAT3 -- Mission 4 stage 3
