Enter these cheat codes at the title screen (or in gameplay, context sensitive) Note: Unlocking stuff do at title, in game stuff like Kill All do in a mission.

Effect	Code
Call ufo	callufo
Kill all	iddqd
Kill boss hallucination	iddqdboss
Print rewired debug	debugrewired
To call terminator	callterminator
To hide ui	hideui
To lock chars back	lockchars
To show ui	showui
Unlock all chars	openallchars
Unlock all levels	phshowalllevels1