The '90s were a magical time for comic books, especially on TV. Shows like Batman: The Animated Series and X-Men raised the bar for Saturday morning cartoons. They showed that superhero cartoons could tell complex, mature and even long-form stories. With their successes came a wave of animation, much of it just as great. Spider-Man: The Animated Series is also generally considered to be a classic, and shows like Iron Man and Fantastic Four eventually found their groove. While things were amazing for most of the decade, things started to fall apart towards the end. Marvel filed for bankruptcy protection, and many of its partnerships fell apart, causing many of their successful TV shows to end prematurely.

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Many of these shows crossed over and featured tons of guest appearances. When the bottom fell out, or at least started to crack, many planned stories had to be scrapped, leaving certain characters in the dust. Other ideas had to be scrapped because TV networks either thought they were too adult for children. Also, networks started becoming ultra competitive over superheroes, and refused to show certain characters they didn't own. No matter the reason, here are 15 planned appearances that should have happened, but outside forces kept fans from getting them.

15 GHOST RIDER IN SPIDER-MAN

Spider-Man and Ghost Rider

Spider-Man: The Animated Series (1994) loved to have other superheroes guest star. Other heroes like Daredevil, The Fantastic Four, Iron Man and even the X-Men showed up, while even some of Marvel's more mature rated characters appeared, like Blade and the Punisher. One notable absence was Ghost Rider, which is strange because he was very popular during the time of the cartoon's production.

It turns out, Ghost Rider was supposed to show up in an episode where he would help Spider-Man fight Mysterio, who would've teamed up with Dormammu. It's been reported, however, that Marvel was trying to get a Ghost Rider series into production on UPN, and since Spider-Man aired on Fox, the network didn't want to promote a rival's property. By the time Ghost Rider's series was off the table, Spider-Man had been cancelled.

14 VAMPIRES VS BATMAN THE ANIMATED SERIES

batman the animated series vampires

Batman: The Animated Series might be one of the most popular renditions of the caped crusader, ever. The show, while made for kids, was able to tell some fairly mature storylines, like the tragic Heart of Ice or Feat of Clay. One idea that was considered just too much for children, however, involved the character Nocturna, who first appeared in Batman #363 (1983) by Doug Moench and Don Newton.

This version of the character would've been a vampire, bringing the supernatural bloodsuckers to Gotham. One plot point of the show would have involved Batman being bit by a vampire and turning into one. Apparently, this was too much for WB, who said no to the episode, as apparently they didn't want children to see Batman craving human blood.

13 SANDMAN IN SPIDER-MAN

Sandman Marvel

During its five season run, Spider-Man: The Animated Series (1994) did a pretty good job of introducing most of the wall crawler's rogues gallery, even including some lesser known villains such as the Spot and Big Wheel. The one major exception was the Sandman, who never appeared in the series at all. Flint Marko is one of Spider-Man's most memorable and longest-lasting enemies, first appearing all the way back in Amazing Spider-Man #4 (1963) by Stan Lee and Steve Ditko.

The issue was that, early in the series' run, there was also a Spider-Man movie in development, and a version of Sandman was supposed to appear as the villain. That movie never happened, and Marko was set to appear in the show's sixth season. Unfortunately, Spider-Man was cancelled after the fifth season, leaving Marko in the dust (or sand).

12 FIRESTAR IN SPIDER-MAN

spider-man and firestar

In 1981, Marvel released Spider-Man and His Amazing Friends, a cartoon which the seemingly random team of Spider-Man, Iceman (from the X-Men) and the newly created Firestar. As silly as the show was, it was popular among fans, and Firestar was eventually introduced into the comics' world in Uncanny X-Men #193 (1985) by Chris Claremont and John Romita Jr.

Spider-Man: The Animated Series (1994) actually cast the voice of the original Firestar, Kathy Garver, for various roles during the show's fourth and fifth seasons. It's rumored that the show's proposed sixth season would have had an episode guest starring Firestar and Iceman, as an homage to the 1981 series. Once again, the show's cancellation is to blame for this never becoming a reality.

11 CAPTAIN AMERICA

Captain America cartoon appearances

One of Marvel's earliest superheroes, Captain America was a popular guest star in many of Marvel's cartoons during the '90s. He appeared alongside Wolverine in an X-Men episode titled Old Soldiers, and he played a central role in the Spider-Man storylines Six Forgotten Warriors and Secret Wars.

In fact, a Captain America series was in the works, and even had a one-minute promo released. Set during World War 2, it would have featured Cap and Bucky teaming up with what appeared to be the Howling Commandos and fighting the Red Skull (although, not Nazis). Unfortunately, the series was a victim of Marvel's 1996 bankruptcy, although that might be for the best because according to the original pitch, Cap was going to be renamed Tommy Thompkins (among other changes).

10 FANTASTIC FOUR IN SILVER SURFER

silver surfer vs thing

In 1998, Marvel released what might be considered its most daring animated series, Silver Surfer. Based on Jack Kirby's style, the series was a departure from typical Saturday morning cartoons. It took a more cerebral approach to storytelling, and often focused on social issues. While it featured many guest stars, the Fantastic Four were notably absent from the Surfer's origin.

Marvel's first family was actually set to appear in the show's second season, which unfortunately never went into production. Apparently, legal issues between Marvel and Saban killed the cartoon, despite having decent ratings. Considering that this cartoon existed in a different continuity than the Fantastic Four cartoon of this era, this appearance would have presented fans with a brand new adaptation of the team, based on Jack Kirby's original comics.

9 FRANKLIN RICHARDS IN FANTASTIC FOUR

franklin richards

Speaking of Marvel's first family, Fantastic Four (1995) was an incredibly uneven show. The first season was heavily criticized for poor animation and a generally campy tone. Both were improved for the second season, which received a much better reaction. While the second season was generally considered a huge improvement, it wasn't strong enough to save the show, which was cancelled in 1996.

Had a third season gone into production, the show planned on introducing Franklin Richards, Reed and Sue's son. He had first appeared in the comics in Fantastic Four Annual #6 by Stan Lee and Jack Kirby, and was born as one of the most powerful beings on the planet. The cartoon would've explored Sue's pregnancy, bringing in characters like She-Hulk and Medusa to fill in on the team. Basically, it sounds like a great story arc that never made it to animation.

8 THE BEETLE IN SPIDER-MAN

Beetle vs spider-man

Another one of Spider-Man's longtime foes that never appeared in the popular Spider-Man: The Animated Series is the Beetle. Abner Jenkins first appeared in Strange Tales #123 (1964) by Stan Lee and Carl Burgos, initially facing off against the Human Torch. He eventually became a regular Spider-Man villain, but was actually another victim of the cancelled sixth season, where he was reportedly set to appear.

The Beetle did appear in Iron Man (1994) during that show's adaptation of the Armor Wars storyline. Since Iron Man and Spider-Man crossed over during the Venom Returns and Carnage two-parter, they technically took place in the same universe. Of course, these rules were loosely followed, so it's not known if the same Beetle would show up or if Spider-Man was going to introduce their own version.

7 THOR IN AVENGERS: UNITED THEY STAND

thor in avengers united they stand

Long before the MCU showed audiences how to do the Avengers right, Avengers: United They Stand (1999) showed everyone the worst way to adapt Earth's Mightiest Heroes. The show was set in the future, the heroes wore weird battle armor (seemingly inspired by Power Rangers) and Iron Man, Captain America and Thor were left off the main team.

While the first two ended up making guest appearances, the God of Thunder never showed up (outside of the opening credits). Thor was, however, included in the toy line and was set to appear in the show's second season. Unfortunately, fans didn't connect with the show and it was cancelled after one season. It seems crazy these days that fans weren't able to see Thor in an Avengers series, but the '90s were a different time.

6 HULK IN AVENGERS:UNITED THEY STAND

hulk avengers united they stand

Another victim of the odd choices made in Avengers: United They Stand (1999) was the Hulk. Bruce Banner and his angry alter ego were also meant to appear in the second season. Apparently, he was going to show up in a storyline that involved the team's leader, Hank Pym, getting sick from gamma radiation poisoning. It's a pretty safe bet that the Hulk would show his face at some point as well.

Hulk was in a different situation than Thor, however. Hulk had starred in his own cartoon from 1996-97, so it's understandable why he was left off the main roster. Still, leaving both Thor and Hulk out shows why United They Stand failed. If more of the popular Avengers had made appearances, even as guests, the show might have last more than just 13 episodes.

5 BETTY BRANT IN SPIDER-MAN

Betty Brant

The sixth season of Spider-Man would have also introduced long time Spider-Man friend Betty Brant. She first appeared in the comics as J. Jonah Jameson's secretary in Amazing Spider-Man #4 (1963) by Stan Lee and Steve Ditko. Originally, she was introduced as a possible love interest for Peter Parker, but that quickly fizzled. They've remained friends (for the most part) ever since, and she's eventually went on to marry Ned Leeds, who was revealed to be the Hobgoblin (until that was retconned years later).

The Hobgoblin story was slightly adapted for the cartoon's third season, with Felicia Hardy stepping in for Betty (and Jason Macendale for Ned). Betty (renamed Brandt) would've appeared as Joe Robertson's secretary, although not much is known about her storyline other than that (although, hopefully another Hobgoblin wedding wasn't in the works).

4 BLACK WIDOW

Black Widow Earth's Mightiest Heroes

While she might be incredibly popular now, Black Widow wasn't a household name back in the '90s. She's been appearing in the comics since Tales of Suspense #52 (1964) by Stan Lee and Don Heck, but she never rose to the ranks of A-list popularity. She was, however, a member of Force Works, which seemed to be the basis for the cast of Iron Man (1994), so there definitely was a place for her.

Her appearance was teased in the intro for the Marvel Action Hour (later renamed the Marvel Action Universe). This was a block of programming that was made up of Marvel cartoons, including Iron Man. Whether or not she was ever intended to appear has never been confirmed, but it seems like there was something in the works.

3 SPIDER-MAN 2099

spider-man 2099

In 1992, Marvel launched a series of comics set in the future year of 2099, including Spider-Man 2099 by Peter David and Rick Leonardi. The line was popular, and eventually expanded to include futuristic versions of other heroes like the X-Men, Fantastic and Ghost Rider. At one point, a Spider-Man 2099 cartoon was in the works, although it never came to fruition.

Essentially, the rights for Spider-Man got very complicated in the late '90s, with Sony and Fox both owning certain aspects of the character. Fox had to revamp their Spider-Man cartoon, and seriously considered using Spider-Man 2099. Unfortunately, Batman Beyond had recently premiered with a very similar look and concept, so 2099 was scrapped.

2 DAREDEVIL

Daredevil cartoon appearances

Another frequent guest star, Daredevil was supposed to take center stage in his own series. In fact, before Netflix launched Daredevil in 2015, studios had been attempting to make Matt Murdock a star since the mid '70s, in both live action and animation. In the '80s, there was even an attempt to make a Daredevil cartoon that costarred Lightning, his crime fighting seeing eye dog (a character who is thankfully, not from the comics).

During the '90s, Daredevil appeared in the Fantastic Four episode And a Blind Man Shall Lead Them and the Spider-Man two-parter Framed/The Man Without Fear. These appearances were meant to launch a Daredevil cartoon. Marvel wanted to wait until the Daredevil movie went into production and launch the series alongside it, however. The film stalled, and apparently took the cartoon down with it.

1 ENEMY ACE IN BATMAN THE ANIMATED SERIES

enemy ace

One of the most unexpected guest stars on Batman: The Animated Series was Jonah Hex. Considering that he's a disfigured cowboy from the 1800s, it seemed unlikely that he could appear in Gotham City in the '90s. The second season episode Showdown, however, told a flashback story about Jonah Hex fighting Ra's al Ghul in the old west, making it possible to include the bounty hunter into the show's continuity.

The show's producers had originally planned to also show Ra's during World War I, fighting against Enemy Ace, a german pilot who first appeared in Our Army at War #151 (1965) by Robert Kanigher and Joe Kubert. It's not clear if this appearance would've been worked into Showdown, with that episode taking place in multiple time periods, or if it would've stood on its own. Either way, it would have helped to expand the history of Batman's immortal foe even more.

Hopefully, Marvel can recapture their success from the '90s with their new animated series Spider-Man, set to debut August 19, 2017 on Disney XD.