X-Men: The Animated Series celebrated its 25th anniversary at the end of October. To celebrate the momentous milestone, the series’ showrunner, Eric Lewald, has written a book titled Previously on X-Men, The Making of an Animated Series that details how the show came together and eventually stayed afloat in an industry that didn’t yet understand the full potential of comic book adaptations. In an interview with Syfy Wire, Lewald also revealed one potential storyline for Season Six, had the show been renewed for another year.

"I had honestly never thought about it for all these years, but now that you mention it, an idea for a season just came to me: The five-season series ends with a dying Charles Xavier being whisked away to space by Lilandra, where she can maintain his fragile body, but where it seems he will be gone forever from his beloved X-Men,” Lewald said. “It's like a death."

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X-Men: The Animated Series was eventually cancelled in 1997, three years before the release of Fox’s first live-action X-Men movie. It’s a move that still baffles fans to this day, as the series enjoyed consistently favorable ratings throughout its run despite the show’s team often lacking adequate funding and time. It wasn’t until 2000, months after Bryan Singer’s X-Men debuted, that the show’s spiritual successor, X-Men: Evolution, started airing on Kids' WB. That show reimagined the X-Men as teenagers, leaving fans to wonder what a sixth season of X-Men: The Animated Series would have looked like.

"Season Six could open, months later, with the X-Men in disarray – a few gone, the ones remaining at each other's throats," Lewald said. "They miss their leader. Then somehow they are called to -- and transported to -- an existential crisis on Lilandra's distant world. The team grudgingly reunites 'for Charles,' heads off to space, solves the crisis and a somehow-healed Charles Xavier is either able to return to Earth with them or, if he can't, his heroic final sacrifice heals the team's wounds and they return to Earth as the proper X-Men again."

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Such a move would have brought the show into Marvel’s cosmic realm once more, a setting fans would have been familiar with since the series touched on the “Dark Phoenix Saga” arc at the beginning of Season 3 and delved progressively deeper into Marvel’s many alien factions. While the likelihood of a sixth season getting greenlit is unlikely, a social media campaign to reassemble the voice cast of the early ‘00s Justice League cartoon has gained quite a bit of traction.