From the introduction: Welcome to the world of Smash Brothers, Jumper! This is a world of combat, where video game legends duke it out. Defeat is not the end here, as Fighters are instead transformed into Trophies on a loss. With reduced stakes, battles have become a means of forging bonds and entertainment. Not all is well. Soon, an antagonist force will lead an assault on this world. This Subspace Army is composed of odd creatures (called Shadow Bugs) and R.O.B.s, with several villainous characters acting as its generals. Its leader, Tabuu, resides in Subspace and desires to pull this world into Subspace in order to rule over it. You arrive in this world an hour before Mario and Kirby battle at Midair Stadium. You will be staying here for ten years, or until the defeat of Tabuu, whichever comes first.