Labs_underpass_p.upk Here

It allows for storing assets inside your level package, essential for functioning with the Rocket League Workshop.

No, you can ignore the universal Mods.upk file for this method. Labs_Underpass_P.upk

This guide will walk you through setting up, testing, and managing custom maps using the Labs_Underpass_P.upk file method. What is Labs_Underpass_P.upk? It allows for storing assets inside your level

Ultimate Guide to Custom Maps in Rocket League: Mastering Labs_Underpass_P.upk Labs_Underpass_P.upk