In Dead Rising 2: Off The Record for the PC, PS3, and Xbox 360, the Protoman Costume is similar to the Megaman costume from Dead Rising, but with a strong attack that shoots three blasts.
Here are the four pieces to the costume, and how to get them.
Protoman Armor – Get The Challenge Experience achievement / trophy by getting a bronze on all single player challenges
Protoman Blaster & Shield – Beat the game with an S Rank by beating Overtime mode
Protoman Boots – In the Ultimate Playhouse in the Palisades Mall
Protoman Helmet – Defeat Jack at Strip Poker in the Ante Up mission, or in Sandbox Mode. Alternatively you can go to the Arena Security Hall in Sandbox mode at 12:00pm on day one and kill him to get it.