Generally speaking, the ambition of a supervillain - besides money and power - is to make their mark. Think of the Joker. Really, he just wants Batman to think about him all the time - which he's probably doing anyways. The X-Men have some of those kinds of villains in their rogues gallery: Magneto. Apocalypse. Any kind of big giant robot.
And like any other superhero team, they have some enemies that have maybe slipped their mind. Not all villains are created equal, and some just don't have what it takes to make an impression. Let's take a look at ten X-Men villains from the 90s the team - and you - have forgotten about.
10 Stryfe
If there was one thing that was overdone in comics in the 90s, it was clones. Stryfe arrived in The New Mutants #87 behind a giant helmet that probably made walking through doors an issue.
There was a little bit of intrigue about who he was, but before long the truth was out: he was a clone of Nathan Summers, AKA Cable. As in Cable from the future... who came back in time to kill his parents... who weren't entirely his parents... or something. Once the cat was out of the bag, Stryfe lost his value as an antagonist.
9 Emplate
As the inaugural villain of '90s X-teens Generation X, Emplate sucked. Literally. He had the creepy ability to suck the life-force of other mutants right out of their bone marrow. Beyond that, he was just a jerk. The first manifestation of his powers killed his mother and then he turned one of his sisters into a diamond-hard mute no one can touch.
A banishment to another dimension made him dependent on a breathing device and also very Sandman-esque in appearance, making him very '90s. He's made some more appearances over the years but otherwise, he dropped down the well of forgotten villains.
8 The Externals
Another product of the X-Force corner of mutantdom, The Externals were an ancient group of mutants destined to help bring Apocalypse to power in the future. Created by Fabian Nicieza and Rob Liefeld, they were most extreme. So, these guys were surely a big deal, right? Nope.
The team never delivered on their promising potential, eventually being wiped out by one of their own, Selene. Unlike most comic book characters and pretty much every X-person ever, they've stayed dead. For that, they deserve some credit. After all, in the Marvel Universe, staying dead is super hard to do.
7 Soul Skinner
Coming at you so extreme in X-Men #17 in 1993, Fabian Nicieza is responsible for this guy as well. A Russian mutant with psionic powers that let him feed off the psyches of others, Soul Skinner was kind of like Omega Red (who we'll get to) but worse apparently, since he turned Red into a puppet.
Soul Skinner tormented the X-Men in Siberia, principally Colossus, who discovers his parents were murdered by Russian agents. Really, Colossus should have seen this coming; anytime someone invades your mind, uncomfortable secrets will be revealed. But then Soul Skinner dies a couple issues later and we never really hear about him again.
6 Omega Red
Red has his fans, for sure, but like The Externals, he never really lived up to his promise. A mutant and product of the Russian supersoldier program, Omega Red possessed heightened speed, strength and agility and some Doc Ock-ish tentacles. But his key power was death spores. That's right. Get too close, and he emits a pheromone that kills you. Probably makes dating hard.
Omega Red was intended to be a major villain for Wolverine, but it didn't work out. He faded into obscurity and ultimately died. But, surprisingly, he got better. People tend to in comics.
5 Random
First appearing in X-Factor #88 in 1993, Random is kind of a blob of white protoplasm most likely created by the Dark Beast who takes the form of a Punisher-like vigilante with an arm cannon. But hey, he was an action figure!
After a run-in with X-Factor over some people called X-Patriots, Random left behind his government contract killing and joined the team for a time. He bounces around from place to place and side to side after that, not quite a hero, not quite a villain, but oh so random.
4 Holocaust
Despite a pretty cool look and a meaty role in one of the X-Men's most famous storylines Age of Apocalypse, Holocaust has not enjoyed quite the same legacy the story has. As one of Apocalypse's sons and one of the Four Horsemen of the Apocalypse, Holocaust was no fun at parties.
He was essentially a giant ball of plasma encased in a specialized suit of armor and couldn't survive outside of it. Though he briefly made the transition to Earth-616 after the end of the story, he didn't last long.
3 Sugar Man
Another product of the Age of Apocalypse who also ported over to the main continuity like Holocaust and Dark Beast, Sugar Man is just bad. Basically a giant head in a leather jacket with four arms, he can smell fear, which probably meant he spent a lot of time sniffing.
Sugar Man always looks like he's having a good time, but he never really does anything. He never gets back to his original reality, he never defeats anybody and he doesn't make for any sleepless nights at the X-Mansion (or Krakoa, most recently). But hey - he's got a sweet new action figure!
2 The Acolytes
Significant mainly for their introduction in X-Men #1, which sold over eight million copies, there were certainly better bad guys to press so much ink on. The Acolytes are some of the worst X-Men villains ever, holding no real distinction and providing nothing of value outside of being cannon fodder.
Messianic followers of Magneto aboard Asteroid M, nothing much came of them in the long run (though they played a part in unleashing Holocaust from his slumber in the 616 reality). That said, one of their numbers - Exodus - surfaced on Krakoa as part of the Quiet Council governing the island in the current House of X arc.
1 Onslaught
Basically Extreme Magneto, Onslaught is the psychic fusion of Professor X and Magneto's personalities, with a serious chip on his shoulder. Not sure how it stays up there, though. After a battle between the X-Men and Acolytes, Xavier mindwipes Magneto, but the Master of Magnetism becomes a mental rock in his old friend's cranial shoe.
This psionic monstrosity kicked serious butt, wiping the floor with the X-Men and banishing the Avengers and Fantastic Four to an extreme dimension, but that didn't last. His place as one of the most '90s - and least remembered - of the X-Men's villains is secure, though.