The new trailer for Marvel vs. Capcom: Infinite reveals a first for the crossover fighting game series: an animated story that explains why the superheroes and street fighters want to pulverize one another.

As the trailer explains, longtime Avengers villain Ultron is joining up (quite literally) with Sigma, the big bad from Capcom’s Mega Man X series, to create a new world in their collective robotic image. The combined duo fuses together into a new form — called, of course, Ultron Sigma — and merge the Marvel and Capcom worlds to achieve their goals using the Infinity Stones, resulting in the various and sundry heroes from both franchises uniting to battle the new threat.

Is this a completely ridiculous way to justify the crossover? Probably. Is it the worst narrative justification of a fighting video game? Not even close.

Along with the teaser for the story mode, the trailer confirms several new characters for the game, including Hulk, Thor, Iron Man, Hawkeye, Rocket Raccoon, Ultron, Chun-Li, Strider Hiryu, and Chris Redfield. Capcom also announced that a Deluxe edition of the game will be available that includes six DLC characters, the first of which will be Sigma (presumably separate from the fused Ultron Sigma version that players will likely battle in the main game).

Along with the new trailer, Capcom confirmed that Marvel vs. Capcom: Infinite will be out on the Xbox One, PlayStation 4, and PC platforms on September 19th.