WARNING: The following contains spoilers for "Crisis on Infinite Earths, Part 2," which premiered Monday on The CW.

Tom Welling made his long-anticipated appearance on The CW's "Crisis on Infinite Earths" crossover event, reprising his role as Clark Kent from Smallville one final time on Monday's episode of Batwoman. His appearance serves as the perfect farewell to the character, in large part because Welling appears as Clark – but not as Superman.

Welling is seen tending to the family farm in the Smallville of Earth-167, when he's approached by Earth-38's own Clark Kent and Lois Lane (Tyler Hoechlin and Elizabeth Tulloch) and Earth-1's Iris West-Allen (Candice Patton), seeking his help to save the multiverse from the threat of the Anti-Monitor and his antimatter wave. However, they barely get to plead their case when Earth-38's Lex Luthor (Jon Cryer) arrives through his multiversal portal. Using his dimensional gateway to whisk the others away from the Kent farm, Luthor stands face to face with Clark, intent on destroying him as part of his mission to rid the multiverse of all versions of Superman.

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Producing a shard of Kryptonite, Luthor is surprised to find the radioactive rock has no effect on Clark -- because Clark is no longer Superman on his world. As Clark explains, he gave up his powers to move from being a superhero to an even more important role: husband and father. Astounded by his decision to willingly give up such power, Luthor doesn't try to take his life, and instead simply departs through his portal. Immediately thereafter, Lois -- this world's Lois, played by Erica Durance, as she was in Smallville -- urges him to come inside at the request of the couple's two (or more) daughters.

That's the extent of Welling's appearance, but it serves as a perfect sendoff for the character. Smallville fans will recall that Welling -- much to the dismay of many viewers -- never donned Superman's iconic costume during the show's run, save for a brief close-up near the end of the series finale. The only scene showing Welling in full costume was computer generated. When Smallville was in production, Welling had repeatedly stated he did not want to wear the costume.

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Smallville ended with Clark taking on the role of Superman, but Welling never played the Man of Steel in the show, or anywhere else thereafter. In fact, there was never real any confirmation that Clark even carried on as Superman -- that is, until he told Lex in "Crisis" that he had given it up. And while no one can arguably fault Clark for giving up the role of superhero to be a full-time father, his decision carries an ironic parallel with that of the actor who played him.

Welling didn't want to wear Superman's costume, and after awhile, neither did Clark. And whatever the career of Earth-167's Superman ever entailed, no one ever saw it. Welling's Clark was never seen in costume, and if Earth-167 ever even had a Superman, viewers only know it because that world's Clark Kent said so.

Earth-167's Superman was exactly the Superman Welling always wanted -- heard of, but never seen. And as such, his appearance in "Crisis" should be only as Clark, and not Superman, because if he was unwilling to take on the role before, there's no reason he should now.

"Crisis," therefore, serves as the perfect farewell to Welling's Clark Kent. He walks, not flies, into that Midwestern sunset, as it should be, content to play the only incarnation of Superman that no one ever got to see.

"Crisis on Infinite Earths" continues in in The Flash on Tuesday, Dec. 10 at 8 p.m. ET/PT. After the winter hiatus, the crossover will conclude on Tuesday, Jan. 14 in Arrow at 8 p.m. ET/PT and in DC's Legends of Tomorrow at 9 p.m. ET/PT.

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