Type in the following code during gameplay:
ALIAH-Invulnerability
FATAL-Gain all weapons and ammo
Use these codes to warp to that level:
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