Brandon Routh is slated to play the Kingdom Come Superman in the Arrowverse's next crossover event, Crisis on Infinite Earths.

"Warner Bros., every time they have a costume, they put it in their archives... and they don't like to let it out. So we won't be able to use your original costume. We're still figuring it out," Guggenheim said during the Arrow Panel at Comic-Con International in San Diego Saturday night.

In response, Routh unbuttoned his shirt to reveal the logo for Kingdom Come's Superman.

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Routh is reported to play both Clark Kent and Ray Palmer, along with joining a returning Tyler Hoechlin as the Men of Steel.

The reveal of Routh as Superman could be the major announcementformer Arrow showrunner Marc Guggenheim teased back in June. "Don't be surprised if we announce something pretty cool at SDCC," he wrote on Twitter.

"Crisis" will be split into five parts, with each Arrowverse show providing a piece of the story: Arrow, The Flash, Supergirl, Legends of Tomorrow and Batwoman. Spanning a whopping five hours, the crossover will air across two quarters, which indicates it will be split over the winter hiatus.

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Slated to air in Fall 2019 on The CW, Crisis on Infinite Earths currently has no announced air date.