Here's a step-by-step guide to getting the One-Punch Man items in Rocket League: Open the Item Shop from the main menu. Go to the Jackal + One-Punch Man tab from the top menu. Select the Bundle or ...

On the Rocket League side, the major rewards are the Fortnite skin Hairpin, which is a very nice recolor of existing skin Pitstop, and a giant Rocket League ball that works as a glider.