Enter one of the following codes during game play to activate the corresponding cheat function.

Effect	Code
Gravity increased by 1 meter/second	[Ctrl] + [Page Up]
Gravity reduced by 1 meter/second	[Ctrl] + [Page Down]
Normal gravity	[Ctrl] + [Page Up] + [Page Down]
Unlimited time for all weapons for each shelter	[Ctrl] + [Home]