The fate of the entire Marvel Universe hangs in the balance as Earth's mightiest heroes face their greatest challenge Summoned across the stars by the mysterious and unbelievably powerful Beyonder, the Avengers, Spider-Man, the Fantastic Four and the X-Men are set against their deadliest foes on the mysterious planet known as Battleworld - with the winner promised the ultimate prize. But as battle lines are drawn, new alliances are forged and old...