i dont know what that cheat is spoed to do!and how do i know its working????help please!

Not sure if this is right, but in MediEvil debug mode removed all enemies and items. Basically you can walk around safely, unless you fall off a cliff, except if you need to hit a swith or go through a doorway it won't work.
Basically the triggers that activate switches or let you enter new areas don't work. At least I think.
Honestly though, debug mode isn't fun. You might think it's great running around with no enemies attacking you at first, but oddly enough it gets kind of lonely and you start to wish there was enemies chasing you.
Also running around doing nothing gets boring quickly.