This looks like Dvar modding.. I think what they did was edit a config file, if you bypass Black Ops and delete you patch, and go into Zombies, you will see there is a option to click "Dev" when you click that it says, "Config String" and the info about it says "Used to make config settings - not used to be played on - Will be deleted when shipped" So this is definalty an ISO mod. Just an Idea for ps3. .self modding and EBOOT.bin editing is the only posible way. :/
Or this could be savedata modding.
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