Batman, Wonder Woman, and Superman. DC's trinity has long defined what it means to be a comic book superhero. They are iconic characters, regardless of the media fans find them in—but DC Comics wasn't built on three characters alone. It is a universe of hundreds of heroes, villains, and supporting characters who have become part of a massive interweaving story that goes back decades.

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A surprising number of those characters did not make their debuts in the comics. In many cases, those characters popped up first in an animated TV series. That wasn't the only place different DC characters debuted, however.

10 Red X Is Finally In The Comics

Red X and Robin on TV

Before the abrupt switch to Teen Titans Go!, fans were engrossed in the Teen Titans' adventures. The series featured Robin, Raven, Cyborg, Beast Boy, and Starfire going up against a variety of villains and their own angst.

For a time, Robin went undercover as Red X—a villainous alter ego he created on the series. A fan favorite, Red X recently became part of the current DC Comics continuity as part of Future State: Teen Titans.

9 The Wonder Twins Were Super Friends Before Comic Friends

The Wonder Twins powering up

DC has a long history of animated series on TV, one of the most classic Super Friends in the early 1970s. It was revived in the late 70s as The All-New Super Friends Hour. It featured a variety of well-known DC heroes as well as introducing some new ones.

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Zan and Jayna were a pair of aliens who went by the name of the Wonder Twins. Zan could become water in any state, while Jayna could become any animal. While they popped up in comic book tie-ins, they didn't appear in the main continuity comics until the 1990s.

8 Livewire Fought An Animated Superman First

Livewire

Pretty much every comic book universe has electricity-based heroes and villains. DC's most famous electrical hero is Black Lightning, a long-time ally of Batman's and a Justice League's key member. Then, there's Livewire.

Introduced in the 1990s as a villain in Superman: The Animated Series, Livewire's electrical abilities were potent enough to take on the Man of Steel. In the mid-2000s, she would leap the comic books and continue her villainous ways.

7 Renee Montoya Was A Cartoon Cop First

Renee Montoya As The Question

Batman: The Animated Series was an incredibly influential series on DC animation and their comics and movies. It introduced some important characters, including Renee Montoya.

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In the series, she was a member of the GCPD who worked under Jim Gordon. Montoya would transition to the comics, becoming a detective and another ally on the force for Batman. Eventually, Renee would even inherit the vigilante identity of The Question from Vic Sage.

6 Nora Fries Went From Popsicle To Villain

Mr. Freeze and Nora Fries from Harley Quinn Animated Series

Mr. Freeze has long been one of Batman's greatest nemesis. A brilliant scientist, he commits cold-related crimes to fund the research he needs to save his wife. Over time, Mr. Freeze just became a criminal, leaving his noble motivations behind.

Nora Fries, his critically ill wife, appeared for the first time in Batman: The Animated Series. She would make her way to the comics, slowly becoming a supervillain who even Mr. Freeze is afraid of.

5 John Diggle Started In The Arrowverse

John DIggle in the Arrowverse

When The CW announced that they were producing a dramatic series loosely based on Green Arrow, fans weren't sure what to expect. As it turned out, Arrow was the starting point for a massive universe of DC TV series referred to as the Arrowverse.

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Early in Arrow, a character named John Diggle was introduced. He started as Oliver Queen's bodyguard but became his closest friend and crime-fighting partner. He would make the transition to the comics as part of the New 52.

4 Barbara Gordon Exists Because Of Batman 1966

Barbara Gordon Batgirl

Commissioner Gordon is a vital ally for Batman. As the leader of the GCPD, he could make things very difficult for the Caped Crusader, but he chooses not to. His daughter, Barbara Gordon, became an even more important ally.

Under the mantle of Batgirl and then Oracle, Barbara could be the most important member of the Bat-Family in the comics. But her journey started in the 1960s as part of the campy Batman series starring Adam West and Burt Ward.

3 Terry McGinnis Was Batman's Animated Successor

Terry and Matt McGinnis as Batman and Robin Beyond

While the war on crime in Gotham might never end, Batman's time at the forefront is limited at best. The man is mortal and will eventually age out of the game. And that's assuming he survives the experience.

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Batman Beyond was an animated series that introduced Terry McGinnis as the new Batman under the older Bruce Wayne's tutelage. He proved to be a prevalent character and would become part of the main continuity of DC Comics.

2 Harley Quinn Is A Key DCAU Alumna

Harley Quinn Is In Suicide Squad

The greatest gift that Batman: The Animated Series gave fans was the introduction of Harley Quinn. She was Joker's former psychologist who fell for him, becoming not only his significant other but also his nefarious criminal sidekick.

Once Harley made her debut in the comics, she went through some incredible changes. These days, Quinn is one of DC's top characters, being featured in comics, TV series, video games, and feature films. And her rise started on one animated show.

1 Jimmy Olsen Appeared On A Radio Show First

a radioactive jimmy olsen reaching out to superman

As a general rule, Superman's associates are a lot more innocuous than Batman's. His supporting cast is rarely highly trained pseudo ninjas who brutally punch criminals in the face. Instead, Superman has a young photographer and reporter named Jimmy Olsen who helps out.

Jimmy Olsen reputedly made an anonymous appearance in a 1938 comic book. Regardless, he wasn't given a name or a full character until The Adventures of Superman radio serial in 1940. After that, it was full steam ahead for Jimmy Olsen, Superman's best pal.

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