We've recently heard about the potential programming that will be available to stream when Disney+ launches in November, and nostalgic fans of Saturday morning cartoons were overjoyed with the inclusion of some of our favorite Marvel comic book cartoons.

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X-Men: The Animated Series helped kick off the 90s wave of superhero animated series and became one of the most popular iterations of the animated X-Men. However, the heroes are really only as good as their villains, so today we are going to take a look at some of the best villains from X-Men: The Animated Series to get ready for our inevitable rewatch when Disney+ launches.

10 SENTINELS

The mutant-hunting Sentinels will be remembered as the first villains the X-Men ever faced in the animated series, arriving with the premiere two-part episode "Night of the Sentinels." The Sentinels were attempting to capture Jubilee, and would apparently kill the X-Man known as Morph, which was a huge moment for a kids cartoon in the 90s.

The Sentinels and their creator Master Mold would reappear frequently over the course of the series, though their threat admittedly grew weaker with each appearance as the X-Men got better and better at destroying them.

9 SAURON

Dr. Karl Lykos is an unlikely character to fall on a best-of list, however, the screeching voice of Sauron always meant that the X-Men were in for trouble on the animated series. It also usually meant that the X-Men were once again visiting the Savage Land, a hidden prehistoric land in Antarctica that was filled with dinosaurs and danger.

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Sauron was an experiment of Mister Sinister's who could absorb the energy of other mutants to become the Pterodactyl-like Sauron. While most of his appearances in the animated series were villainous, when he was in his human form, he lived peacefully as a member of Ka-Zar's tribe.

8 GRAYDON CREED

It's easy to forget the impact the leader of the Friends of Humanity had on the animated series, considering all of the great superpowered villains that appeared over five seasons. However, Creed's bigotted dedication to his organization continually reminded the X-Men that humans were willing to go to extremes against them as well.

Creed's mission would become even more personal when his heritage was revealed. Graydon was the human son of two mutants (Sabretooth and Mystique), and his increasingly out-of-control plans to take out humanity cost him everything, including his precious Friends of Humanity.

7 MYSTIQUE

Graydon's mother played that role to a few other X-Men in the animated series, and her familial ties with Rogue and Nightcrawler would be explored throughout her many appearances on the animated series.

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It wasn't only the depth to which her character was explored in the series that make her one of the best X-Men villains, but also the fact that she's just so villainous on the show. Not only does she work with Apocalypse, Magneto, and Mister Sinister, but she also led the Brotherhood of Evil Mutants and almost caused the "Days of Future Past" timeline.

6 MOJO

For a character with so few appearances in the animated series, it might be hard to see why Mojo is so high on this list, but everything about the character was fun to watch. he was so incredibly bad, yet always focused on entertaining the audience.

His gross appearance was coupled with fantastic voice work from Peter Wildman that still plays in our head when reading through any of Mojo's comic appearances. Mojo might even be more appreciated now by adults than he was when we were kids, given some of the jokes and references in his episodes.

5 SABRETOOTH

Sabretooth has appeared in every iteration of the animated X-Men (except for the Pryde of the X-Men pilot), but he has never been as fleshed out as he was in X-Men: The Animated Series. Multiple episodes were dedicated to exploring the rivalry and history between Sabretooth and Wolverine, including revisiting the Weapon X program that experimented on both of them.

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Sabretooth's history with Mystique and their son Graydon was also briefly touched on, though that was more explored with Mystique than Sabretooth. It is interesting to note that in the animated series his name is Graydon Creed Sr. instead of Victor Creed, to reinforce his parentage of the hateful young Graydon Creed.

4 JUGGERNAUT

Cain Marko is one of the first villains encountered by the X-Men during their first season, and they quickly learn of his relationship with Professor Charles Xavier. Juggernaut didn't appear that often on the show, but he remained a fan-favorite due to his cheesy lines and feats of strength.

The animated series even featured another character as the Juggernaut, after Cain Marko loses his abilities. The new Juggernaut, Eugene Weiderspan, only holds the powers for a short period as the X-Men were forced to return the powers to Cain Marko, who was dying without them.

3 MISTER SINISTER

One of the most sinister villains on X-Men: The Animated Series was, quite appropriately, Mister Sinister. The evil geneticist first appeared fully in the episodes "'Til Death Do Us Part," which revealed his obsession with Scott Summers and Jean Grey.

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Those episodes also revealed his manipulations of the presumed dead Morph into his agent, and Morph would then spend the rest of the series tragically fighting off Sinister's influence. Sinister's Victorian origins were even explored in the episode "Descent," though his connection to Apocalypse wasn't touched on in the animated series.

2 MAGNETO

Magneto has been both enemy and ally to the X-Men, and he was represented much the same way in X-Men: The Animated Series, though he played the villain role more often than not. Magneto was the next big villain the X-Men faced in the series, after the two-part episode that introduced the Sentinels.

Magneto and Xavier's relationship was also explored heavily in the series, both in the past and in the present, and the two often found themselves working together in the series against larger threats. Interestingly enough, despite Magento's comic affiliations and teams, he usually worked alone in the animated series.

1 APOCALYPSE

Apocalypse would become a looming threat to both mutants and humans over the course of the series, following his first appearance in the episode "The Cure." His animated appearances began with his transformation of Angel into Archangel, though Warren's role with the animated X-Men was not the same as his comic counterpart.

Apocalypse would also feature heavily into some of the larger multi-part episodes like "Beyond Good and Evil" that explored the timestream and alternate realities. His evil would span into the future as well, resulting in the appearance of fan-favorite Cable in the animated series.

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