Ultimate X-Men Vol. 5: Ultimate War

The Ultimate's vs. the Ultimate X-Men: the battle begins. When the X-Men do the worst thing they could to humanity; the government orders Captain America; Iron Man; Thor and the rest of the Ultimate's to bring them down. A small but lethal army; the Ultimate's were created to face these and other newly rising threats to mankind. But the X-Men's founder; Professor X; hasn't been training his students for nothing - and the young's mutants just might take out the Ultimate's first.