Original URL: http://www.psxextreme.com/ps2-cheat-print/258.html
Rogue Ops

Half damage:

Pause the game, then press Square(2), Circle(2), Left(2), Right(2), Circle(2), Square(2). If you entered the code correctly, the screen will flash white and a whooshing sound will play. Note: This must be entered quickly and at a steady pace.

Thanks to RamirezXsJ