Looking ahead to Fox’s X-Force movie, Rob Liefeld explains that he created the violent X-Men offshoot because he was bored of Charles Xavier’s gifted youngsters.

When X-Force first appeared at the end of New Mutants #100 in 1991, the X-Men had already been established for nearly three decades. Described as having a more militant approach than the classic roster of X-Men heroes, Liefeld and Fabian Nicieza’s team went on to sell more issues than anyone expected.

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Speaking to Fandango, Liefeld explained that he was tired of the mundane adventures of the X-Men and wanted something with a more violent streak.

“You know, back when I created X-Force, as a fan I was kind of tired with the X-Men. They had become what I would say kind of a mopey group. A mopey bunch of people. They were always drowned in their own sorrows, and I like action — I like kick ass characters.”

After Liefeld revamped the New Mutants title with writer Louise Simonson, he and Nicieza promoted members like Boom-Boom and Warpath to X-Force under the leadership of the mysterious Cable.

“When I transformed the book and turned it into X-Force, I think each of the characters, from Cable to Domino to Deadpool are a kick ass group of badass mutants that don’t take any sh*t. They knock down your wall. They ask questions later. They are very much a more aggressive arm of the X-Men.”

“I took a book that was selling a hundred thousand units, and the last issue that introduces X-Force sold one million units, and that was a 14-month journey,” Liefeld recalls, explaining why he believes it became one of Marvel’s biggest sellers, ever. “It is the second best-selling comic book of all time for a reason. People rallied around it. I mean, my X-Men had weapons. They had attitude. They had aggression. I just felt like somewhere between Xavier’s pacifists views and Magneto’s terrorist views there had to be an activist view. So you had pacifist and terrorist, and I introduced a much more aggressive arm of the X-Men.”

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Originally called the X-Terminators, Liefeld still has the fax from 1990 when his plans for the team were originally turned down. He admits that it’s been a hard grind to bring the likes of Deadpool and Cable to life, but reiterates that it was worth the effort, and he hopes the team will get a resurgence in the Foxverse.

Directed by David Leitch, Deadpool 2 stars Ryan Reynolds as Deadpool, Brianna Hildebrand as Negasonic Teenage Warhead, Leslie Uggams as Blind Al, Stefan Kapičić as the voice of Colossus, and Karan Soni as Dopinder, with newcomers Zazie Beetz as Domino, Josh Brolin as Cable, Julian Dennison in an unknown role, and Jack Kesy as a villain widely thought to be Black Tom Cassidy. The film hits theaters on May 18.