X-Men vs. Avengers

The Black Knight detects satellite fragments falling to Earth, and the Avengers act quickly to save lives at an American mall. Meanwhile, Magneto also detects them, and correctly identifies them as fragments of Asteroid M. He leaves the X-Men to collect a fragment on his own, but the team follows him. The X-Men soon find themselves facing off against the Soviet Super-Soldiers and the Avengers, as both of those teams want Magneto to be tried and/or punished for his past crimes.