WARNING: The following contains spoilers for the Season 7 finale of DC's Legends of Tomorrow.

The Season 7 finale of DC's Legends of Tomorrow saw one of the Legends retire from being a superhero.

Actor Nick Zano joined Legends in Season 2 as Nate Heywood, a historian who became superhero Citizen Steel when he gained the ability to turn his body into steel. As Season 7 culminates with the time-traveling team of misfits rescuing a loved one from World War I, Heywood loses his steel powers running through a cloud of highly corrosive mustard gas. "It felt like a natural way to end his run on the show," series co-showrunner Keto Shimizu told TVLine. "He began the show by gaining the superpower. It felt right that he say goodbye to it as he’s saying goodbye to the team."

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The penultimate episode of Season 7 featured the various Legends being shown glimpses of their respective futures in an attempt to lure them away from time-traveling superhero antics. As the series has not been confirmed for an eighth season, the flashes forward provided a possible sendoff for the team. Heywood, shown his successful author future-self, particularly struggled with the thought of transitioning from action hero to academic. Taking the loss of his powers as a sign, he opts to retire and write a book about the history he has witnessed first-hand.

"It really made sense, to us, that he would probably never feel like his job was done as long as he still had that ability," Shimizu said. "We wanted him to literally go out there and give it 100 percent. And in this case, he does that and more... he becomes a regular mortal man again. But now he knows that he did everything in his power to do this act of heroism."

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Zano is confirmed to be stepping down from the main cast, but if previous character and actor exits from the show set any precedent, he could easily pop up again. The ensemble cast has rotated through many permutations over its seven seasons, and retired characters have returned for cameos in both Legends and other Arrowverse shows. Using shapeshifting and alternate timelines as plot devices — and old-fashioned makeup and prosthetics in one case — three different actors have played multiple main characters in different seasons.

While The CW has not yet confirmed a new season, the Legends Season 7 finale ends on a cliffhanger and introduces a possible alchemical replacement for Citizen Steel with the apparent debut of Booster Gold, played by Scrubs star Donald Faison. Should a Season 8 be greenlit, Legends remains poised to be the Arrowverse's showcase for DC's obscure, wacky and otherwise C-list superheroes.

DC's Legends of Tomorrow airs on The CW.

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Source: TVLine