An interdimensional being plans to merge all of the multiverse into one, which will cause a cataclysmic event that will tear the fabric of reality. Fearing that Earth's Mightiest Heroes and The Guardians of the Galazy will try to stop the being, the being tries to separate them into different universes so they won't be a knewsince to it's plan and they'll probably die in the merge. Along the way for The Avengers and the Guardians, they encounters old friends, powerful enemies, new allies and unite to save the multiverse: