In the mml folder create a file named cheats.mml (or anything really). copy this in the file then save it:

To use the cheat codes, type them in while pressing "control". Weapon and ammo cheats will indicate their success by the "picked up item" sound and effect. Here are those cheats:

nrg: add suit energy
otwo: add oxygen
map: show items, monsters, and projectiles in map view
bye: invisibility
nuke: invincibility
see: infravision
wow: extravision
mag: pistol
melt: fusion gun
puff: shotgun
rif: rifle
zip: SMG
toast: flamethrower
pow: rocket
pzbxay: alien gun
ammo: lots of ammo