Press [~] (tilde) to display the console, then type:
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playbetter – invulnerability
twoweeks – Increase Energy
meatwagon – kill all monsters
victor – kill all monsters including the boss
angermonsters – evil monsters
crazymonsters – monsters seek blood
kiwi – walk through walls
showcoords – see coordinates
weapprev – previous weapon
weaponnext – next weapon
suckitdown all – get all weapons, spells and accessories
spawn (name) – create an item
map (name) – go to the map