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Another new team member will join the crew of the Waverider next season, but according to executive producer Marc Guggenheim, DC's Legends of Tomorrow won't be bringing the character in from the comics.
Instead, Guggenheim told Rotten Tomatoes, the series will mine from other media, introducing an established DC character...but one who didn't originate in the comics.
There are quite a few of those, although some -- like Livewire, Jimmy Olsen, and Perry White -- have already appeared on Supergirl, and Guggenheim suggested the character would be new to the shared DC multiverse of The CW.
"We’re drawing on an established character who is not from the comics," Guggenheim said. "Let me be very clear: not original to the show but not from the comics and not from any of the other DC Arrowverse shows."
Characters who have originated in other media and gone on to be memorable parts of the DC Universe's mythology include (pictured above) Harley Quinn from Batman: The Animated Series, Isis from the 1970s Shazam!/Isis Hour, Renee Montoya (Batman: The Animated Series again) and Black Vulcan from Super Friends, which has been referenced often on Legends of Tomorrow.
Montoya has appeared on Gotham, which is live action DC, but not part of the Arrowverse. Harley Quinn appeared -- although they did not use her name or costume -- in an episode of Arrow. Both Isis and Black Vulcan seem unlikely because of the Shazam! and Black Adam movies, and The CW's upcoming Black Lightning TV series, respectively.
Smallville, of course, might be fertile ground for something like this to draw from: characters like Tess Mercer, Chloe Sullivan, and Dr. Curtis Knox, who was remarkably similar to Legends of Tomorrow season 1 villain Vandal Savage and who was played on Smallville by Lois & Clark: The New Adventures of Superman co-lead and Supergirl villain Dean Cain.