No cheat code exists for instant Level 50 in Dead Rising (Xbox 360). The game has no cheat console or code entry system.
Play Infinity Mode with Sledgehammer (Leisure Park, near entrance) or Mini-Chainsaw (Hardware Store, Paradise Plaza). Circle the mall, kill everything, eat from restaurants. 2–3 hour sessions yield 100k+ PP.
No shortcuts—Dead Rising rewards mastery of its systems. The grind is the game.