Marvel's X-Men: The Seminal Moments documentary series continues with a look back at the massive Age of Apocalypse crossover.

In 1995-1996, Age of Apocalypse spanned the entirety of Marvel's X-Men titles, replacing each regularly published series with a new, appropriately branded miniseries. The event saw Legion accidentally kill his father, Professor X, causing Apocalypse to unleash a deadly attack a decade sooner than he would have in the original timeline. As a result, he's able to take control of Earth, and several factions of mutants unite to take him down.

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"I don’t think I ever saw an overview, it was that loose," Larry Hama, one of the many writers involved in Age of Apocalypse, said. "It was this great sort of jazz improvisation. You were making it up as you went along and riffing on everybody else's riffs. It was good because it gave a lot of top creative people at the time free reign to just run with their imaginations."

X-Men: The Seminal Moments is being released in anticipation of House of X and Powers of X, which are written by Jonathan Hickman and illustrated by Pepe Larraz and R.B. Silva, respectively, as the two titles promise to change everything readers know about Marvel's Merry Band of Mutants.

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House of X #1 and Powers of X #1 go on sale in July from Marvel Comics.