Whilst re-entering most "mode"-style cheats (ones that toggle something on or off, like slow motion for instance) will bring up a "Cheat Deactivated" notification, we often found when testing them out that this didn't do anything and the cheat remained active until we quit the game or reloaded a save. This is an obvious one, but make sure you always save before entering cheats, just in case something goes wrong and you cause a little too much havoc. As such, use a separate save file for any cheat-filled sessions.
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However, in our experience the ones which work and which don't can vary - so if one code doesn't work one way, try the 'usual' method for that platform to see if that works instead.
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This means on PC you can use controller input to activate cheats (useful for the new Big Head Mode in particular!) and on console, use the PC keyboard inputs to activate cheats.
There is seemingly no PC-specific way to input this cheat by using a keyboard. One is Big Head Mode, which is performed by entering the Konami code (Up, Up, Down, Down, Left, Right, Left, Right) then the right-most face button, then the down-most face button (so on PlayStation, would be Circle then X).