Dr Wily builds a machine that goes horribly wrong and sends everyone to the future, so X and Zero meet Rock and Blues. And Dr Wily teams up with Sigma and the hero's have to stop them. Along the way they meet new friends.
Zero arrives at the final battle with Omega, and he finally gets all his memories back from his past before he was put to sleep. (Rated T due to blood.)
Takes place in the Megaman X3 ending, X is feeling worried about the future and how he might have to fight Zero so Zero tries to cheer his friend up. (X and Zero bromance :P, cause they aren't gay... sorry that's the truth :3)
The three best friends have a reunion after the Blue Bomber is chosen to be in the new Super Smash Brothers, and they have a day full of fun.