Overtime Mode is back in Dead Rising 2 for the PS3, Xbox 360, and PC. You unlock it in a similar fashion to the original Dead Rising as well.
To unlock Overtime Mode in Dead Rising 2, you need to complete all cases, give Katey her Zombrex dose every 24 hours, and give Zombrex to TK before the final fight begins. If you do that and complete story mode, you’ll enter Overtime Mode where TK will give you items to collect for him, and you’ll have an extra block of time to play with.
Finishing Overtime Mode will get you the “Justice Served” achievement/trophy.
