Cheat mode
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Result - Code:

God mode in last level - iamgoddess
Kill onscreen enemies - giants
Toggle flight mode - enabled fly
Land in flight mode - active drop
List weapon names in debug mode - all weapons
Obtain indicated item - gimme (item name)
Remove fog - foghack
Switch view to nearest enemy - switch
Unlock doors - opensezme
God mode - iamgod
Full health - smoghead
Enable debug mode - debug on
Disable debug mode - debug off