Jonathan Hickman accidentally shot himself in the foot while helping write Avengers vs. X-Men, aka AvX. The writer revealed as much during his panel at Comic-Con International in San Diego, where he took a few minutes to look back at his work on the crossover.

Hickman was one of the many writers who worked on AvX, Marvel Comics' 2012 crossover that pitted the two superhero teams against one another. By the point they reached his issue, Hickman introduced the restructuring of society brought on by the Phoenix Five. Along the way, he introduced Charles Xavier to the story as someone who doubted what his former students were doing.

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"I was in the room when we decided to kill Charles Xavier in [AvX]," Hickman told Comic-Con attendees. "And I was like, 'No, don't kill Charles!' He wasn't in the main series, I brought him in issue #6 when we did the mutant society building. That turned him into dying, which kind of screwed me because I wanted to use him in New Avengers as a part of the Illuminati. They were like, 'No, that's a perfect ending!'"

Xavier wouldn't stay dead for long, with his brain being stolen by the Red Skull in Uncanny Avengers and Xavier eventually being resurrected thanks to Fantomex in Uncanny X-Force. Xavier is set to play a major role in the future of the Marvel Universe in the pages of Powers of X and House of X.

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House of X #1 is in comic stores now, with an issue of either Powers or House following on a weekly basis. House of X is written by Hickman, with art by Pepe Larraz, and Powers of X, also written by Hickman, is illustrated by R.B. Silva. Both series will feature color art by Marte Garcia.