Tom Welling had a cameo appearance in The CW's "Crisis on Infinite Earths" event, where he reprised his Smallville role as Clark Kent. Clark no longer had the powers of Superman, though, and the event's showrunner explained the reasons why, saying part of that is a tribute to a classic Superman film.

"We also discussed a nod to, believe it or not, Superman II," Marc Guggenheim told Fake Nerd Podcast. "It wasn't relevant to the story that we were telling in terms of getting into the specifics of it, and there are certain things that I believe are best left for the fans to discuss and debate."

"I don't believe in giving the fans the entire picture all the time," Guggenheim added, "But the idea that Clark would give up his powers in order to have this kind of life, that really resonated with all of us, and I think it really resonated with Tom [Welling]. It just makes sense."

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Welling's character took on the mantle of Superman in the final episode of Smallville's 10-season run, but was never seen in costume after that. That version of the character didn't appear again on television until "Crisis," where he revealed he had already given up his powers in favor of being a full-time husband and father.

In Superman II, Christopher Reeve's version of the character also gave up being Superman, albeit temporarily, for similar reasons.

"It was one of the reasons why it was so important for us to show you those Daily Planet articles that Lois wrote," Guggenheim said. "We very much wanted to tell the audience that the promise of Smallville was, 'He's going to become Superman.' We wanted to make it very clear that that did happen, that he did become Superman, that he did have all these adventures, but they are left to your imagination."

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