To enable the cheat mode, press Ctrl+Alt+~ and the console window will be activated. Then use one of the following codes you see below to unlock the secret function you need.
God mode and infinite Spirit mode: god
Get all weapons with max ammo: give all
Unlock no clipping mode: noclip
Get no damage from enemies: notarget
Get health: give health
Refill ammo for all weapons: give ammo
Use the following tip to get the indicated object! Enter the code give [name] in the console window and use one of the items instead of [name]:
weapon_wrench
weapon_bow
weapon_rifle
weapon_hiderweapon
weapon_autocannon
weapon_rocketlauncher
weapon_soulstripper
weapon_crawlergrenade
monster_centurion
monster_fodder
monster_hound
monster_hunter
monster_mutate
ammo_autocannon
ammo_rifle
ammo_autocannon_grenade
ammo_acid
ammo_lifeforce_small (+ 8 points of lifeforce energy)
ammo_lifeforce_medium (+ 12 points of lifeforce energy)
ammo_lifeforce_large (+ 25 points of lifeforce energy)
ammo_lifeforce_wraith (+ 100 points of lifeforce energy)