The icons of comic books, DC and Marvel, have given the world some of the greatest fictional characters in history. These characters have been so influential in pop-culture, they've generated movies, television shows, and even influenced how the public dresses. Most of these characters were introduced way back when in their respective comics.

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Some have morphed over time. Batman, for instance, began as lighter-hearted in terms of character but killed people. He's now a dark, brooding vigilante who has a strict "no killing" policy. Some of the characters have become so pivotal within the comic book landscape, it's hard to imagine a world without them. Strangely, some didn't get their start on the pages.

Perry White (DC)

Perry White holding a newspaper in Action Comics #1002.

Perry White is synonymous with Superman. He's the hard-nosed editor and chief of the Daily Planet. He's become a foundational aspect of Clark Kent and Lois Lane's working life. Interestingly, his first appearance wasn't an appearance at all.

Perry White was introduced during The Adventures of Superman radio show in 1940. The character would later be written alongside Superman in Action Comics, becoming his lifelong boss. Since his creation, Perry White has gone on to be a part of animated series, television shows, and films.

Nora Fries (DC)

Mr. Freeze is an iconic Batman villain, filled with personal torment and anguish over the loss of his wife, Nora. Freeze's wife got her start in the famous Batman: The Animated Series, back in 1992. She wouldn't make her way into comics until 1997.

Nora Fries is the reason Mr. Freeze does what he does. She may not be the character with great lines or a commanding stage presence, but she is the driving force behind one of Batman's most dangerous enemies. He's ruthless, calculating, and won't hesitate to kill anyone who stands between him and Nora.

Spyke (Marvel)

The year 2ooo saw the release of an ambitious new animated series called X-Men: EvolutionThe show would follow the exploits of a younger and inexperienced X-Men in high school. Among the cast was a young mutant with the peculiar ability to produce spikes from any part of his body.

This would be the first appearance of the character Spyke. Though the character would never make much of an appearance on the silver screen, the character Kid Omega from X-Men: The Last Stand would be heavily influenced by the abilities of Spyke.

Mercy Graves (DC)

Behind every megalomaniac is an equally homicidal woman. Mercy Graves is the head of security and chauffer to Lex Luthor, archnemesis of Superman. Fans were given their first taste of Ms. Graves in  Superman: The Animated Series. Unlike Nora Fries, Mercy would quickly be added to the comics in 1996, the same year she made her debut on the animated series.

A former thief, Mercy Graves met Lex Luthor after having stolen from him. Noticing talent when he saw it, Luthor offered Mercy a job where she would serve as Lex Luthor's enforcer.

Livewire (DC)

Livewire made her mark on the comic book world when she was introduced in Superman: The Animated Series. Leslie Willis started out as a shock jock personality with a real dislike for Superman. In an attempt to save her life, Leslie was electrocuted by a stray cable during a concert event.

A bolt of lightning hit Superman, ran through the cable, and hit Leslie. This would turn her into the meta-human villain fans know as Livewire. It wouldn't be until 2006 when the character would make her first big comic book appearance.

Abraham Whistler (Marvel)

Fans immediately recognize this name from the Blade franchise starring Wesley Snipes. Abraham Whistler is a vampire hunter who took Blade under his wing and trained him. The character made his very first appearance in Spider-Man: The Animated Series in 1995.

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The character eventually found his way to comic books in 2002. By this time, Whistler had already made it to the silver screen with the release of Blade in 1996. The character's cartoon backstory would remain essentially the same as the film adaptation.

Terry McGinnis (DC)

Batman Beyond tells the story of a young man who would come to don Batman's cowl after old age and illness would no longer permit Bruce Wayne to carry out his war on crime. McGinnis would be a far less menacing figure than his predecessor, but would nevertheless be the hero Gotham needed.

Justice League Unlimited eventually explained Terry McGinnis was actually a clone of Bruce Wayne. This iteration of Batman first aired in 1999. That same year he would make his splash on the scene with the comic book world with his very own series.

Harley Quinn (DC)

Harley Quinn smiling in Batman TAS

Harley Quinn has earned herself a special place in the hearts of comic book fans across the world. She's funny, demented, and she's the backbone of the Joker. The character was first introduced in 1992 on Batman: The Animated Series.

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The following year would mark her comic book debut. Since her debut, Harley Quinn has become part and parcel with the Joker, at once causing him undeniable annoyance and also a loving hand. It can be said she was literally made for him. She has since been seen on the big screen played by Margo Robbie.

X-23 (Marvel)

X-23 Intro

X-23 is a copy of Wolverine. She was cloned and possesses every one of Wolverine's abilities. She was created by Craig Kyle and Christopher Yost for X-Men: Evolution. She made her appearance as an assassin who systematically took out everyone in the X-Mansion until only Wolverine was left.

She blamed Wolverine for how her life turned out. The scientist who made her, Deborah Risman, would eventually be changed to Sarah Kinney when her character made her transition to comic books in 2004. The character, named Laura, would be introduced in Logan starring Hugh Jackman.

Jimmy Olsen (DC)

Jimmy Olsen is an odd one. There was an unknown character who appeared in 1938 in Action Comics. However, it wasn't until 1940 when the character would be given a name, Jimmy Olsen. The following year the character made the move to comic books.

Jimmy is a photographer for the Daily Planet who often teams up with Clark Kent and Lois Lane. In recent years he's been played by Mehcad Brooks on Supergirl. The character is decidedly different, taking on a very powerful role, even going as far as doing armor and becoming a masked vigilante.

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