You and 3 other people have been summoned to be the hero's of the kingdom. You wake up in front of the King and he tells you that you're the new hero's. You spawn in with whatever weapon you want but the other three will have other weapons. You and the 3 other hero's have to save the kingdom and maybe the world.

This is during the Shinjuku Showdown. Gojo hasn't been unsealed yet but he will soon. I wormhole appears in the sky and a bunch of people walk out including you. However your enemy walks out as well you all scatter. Be whoever, have whatever techniques you want or if you your own technique.