Mega Man ZX Advent preview at 1-up.

"Mega Man may be dead, but his spirit lives on. That's the premise of Mega Man ZX Advent, anyway -- the sequel to last year's free-roaming successor to the ultra-hardcore Mega Man Zero games, Advent is the closest thing you're going to see to Mega Man's classic NES outings...even if the Blue Bomber himself is nowhere to be seen.

See, Mega Man was replaced by Mega Man X, who fought for everlasting peace for a few centuries before sacrificing himself to put an end to a war while his buddy Zero carried on the good fight. Eventually Zero died nobly as well, and their robo-essences became "Biometals," sentient devices capable of transforming humanoid users into their spitting images. It's complicated. The important thing to know is that the main character of Advent -- well, characters -- comes across a hunk of Biometal called Model A, as well as a pair of Biometal-huntings warriors named Prometheus and Pandora who hope to lay claim to Model A themselves."

Full Source: 1-up