When it comes to starting rosters, few animated shows can compete with the original aliens of Ben 10. One of the most beloved cartoons of the 2000s, Ben 10 told the story of a young boy who becomes wrapped up in countless alien adventures after he fuses with the Omnitrix, an impossibly powerful piece of technology that could transform him into a variety of extraterrestrial life-forms. Ben 10 spawned countless spin-offs and sequel series, even inspiring a live-action film, but the original run of episodes starting in 2005 remains the most iconic.
Part of what made the first series so strong was Ben’s well-balanced roster of the original ten aliens. Though Ben would go on to unlock many more forms over the years, these first ten aliens were varied enough to give the boy superhero an answer to any situation while never seeming too outlandish or over-specialized. Every member of Ben’s starting lineup was useful to some degree, but there are some clear winners in terms of the strongest powers, character designs, and overall memorability.
10 Ghostfreak
First Appearance: Season 1, Episode 4 “Permanent Retirement”
Capable of flight, telekinesis, intangibility, invisibility, and possession, Ghostface was one of the most powerful aliens Ben originally had access to. However, he was incredibly dangerous to use, with the consciousness of the alien warlord Zs’Skayr inhabiting the Omnitrix’s sample of Ghostfreak’s species. Zs’Sakyr would slowly influence Ben’s actions while in the form of Ghostfreak, making the terrifying spectral alien a risky choice, despite his power. As cool as Ghostfreak was, Ben ultimately wasn’t able to control him, losing the form to Zs’Sakyr as he escaped the Omnitrix.
9 Ripjaws
First Appearance: Season 1, Episode 3 “The Krakken”
The most specialized of Ben’s original ten aliens, Ripjaws is an aquatic beast capable of tearing through steel with his powerful jaws. Ripjaws is also able to morph his legs into a single, merman-like tail, allowing him to swim incredibly fast. Of course, the aquatic alien is a very specialized tool in Ben’s arsenal, excelling underwater but being near-useless in other environments, as prolonged time on dry land dehydrated him to dangerous levels. Ripjaws is good at his job, but isn’t versatile enough to stand with the best of Ben’s other options.
8 Stinkfly
First Appearance: Season 1, Episode 2 “Washington B.C.”
Perhaps the grossest of all of Ben 10’s aliens, Stinkfly is most notable for the putrid, sticky slime he is able to squirt from his snail-like eye stalks. The insectoid alien also has a suite of other bug-like powers, including a razor-sharp stinger, hover-capable wings, and the secretion of a powerful toxic gas. Not a pleasant alien to be around, Stinkfly’s abilities are seldom more useful to have than other aliens in the Omnitrix, being outperformed by fellow fliers like Heatblast and Ghostfreak in terms of raw power, making him one of the least-used aliens in the original Ben 10 run.
7 Upgrade
First Appearance: Season 1, Episode 4 “Permanent Retirement”
One of the most striking-looking aliens, Upgrade is actually a swarm of nanomachines forming a collective hive consciousness into a single alien entity. As such, he’s able to wrap his amorphous body around machines, controlling and “Upgrading” them to suit Ben’s needs. Upgrade is still useful on his own, able to form crude weapons out of his body and even fire a laser from his eye, but thrives in the presence of machinery or against robotic opponents. Outside such circumstances, its unlikely that Upgrade would be Ben’s best choice for heroics.
6 Heatblast
First Appearance: Season 1, Episode 1 “And Then There Were 10”
The first alien Ben ever transforms into, Heatblast is a staple pick Ben would utilize many times throughout the original series. A fiery being with the effortlessly cool voice of VO legend Steven Blum, Heatblast’s pyrokinesis is surprisingly versatile, able to use his staggeringly hot flames to fly, melt steel, and form massive tornadoes of fire. The rock-like formations on Heatblast’s body also allude to his limited geokinesis, giving him control over more than one element. However, the alien’s potential for unintentional destruction and his vulnerability to flame-retardant enemies made him difficult to work with at times.
5 Grey Matter
First Appearance: Season 1, Episode 2 “Washington B.C.”
Grey Matter might not seem like much at first glance, as a diminutive alien with no obvious special powers. However, the Galvan race Grey Matter represents are known for their incredible intellect, granting Ben enhanced powers of deduction, technological capabilities, and feats of engineering when assuming the form of Grey Matter. His ability to solve practical problems is unmatched by any other alien in the Omnitrix, and his small stature can be useful for making daring escapes and subterfuge. While Grey Matter can do things no other alien can, he admittedly isn’t much use in a fight.
4 XLR8
First Appearance: Season 1, Episode 1 “And Then There Were 10”
The resident speedster of the Omnitrix, XLR8 is an alien-life form that lives life in the fast lane, able to rush down Ben’s foes with blazing speed. XLR8 doesn’t simply run fast, but manipulates friction itself, allowing Ben to stop on a dime before instantly accelerating to blistering speeds. Ben’s reaction times are similarly enhanced as XLR8, giving him an inherent advantage in dangerous situations with the ability to think quickly. Complete with a natural visor that keeps the wind out of his eyes, there are few situations in which XLR8 wasn’t a good choice for Ben to use.
3 Four Arms
First Appearance: Season 1, Episode 2 “Washington B.C.”
One of Ben’s most-used alien forms, Four Arms proves that sometimes simplicity is best. A hulking red giant with two sets of powerful arms, Four Arms is Ben’s physically-strongest aliens, able to come to blows with just about any enemy the series threw at him. He’s also insanely durable, able to to tank all manner of physical attacks as well as brave extreme temperatures and even radiation. With his iconic simple design and universally useful powers, it’s no wonder that Four Arms was one of Ben’s most preferred options to use.
2 Wildmutt
First Appearance: Season 1, Episode 1 “And Then There Were 10”
An incredibly well-rounded alien, Wildmutt was somewhat underutilized by Ben in the original series, despite the canine species’ many impressive strengths. With strength rivaling Four-Arms and agility nearly as good as XLR8’s, Wildmutt was a jack-of-all-trades whose most powerful feature was his delicate senses of smell and hearing. Though not having eyes, Ben was able to use Wildmutt’s senses to sniff out invisible enemies and pefectly map his environment. Equally at home leaping from tree to tree or burrowing through the Earth, there were few situations that Wildmutt couldn’t adapt to, the only major drawback to him being that he was the only form Ben couldn’t speak in.
1 Diamondhead
First Appearance: Season 1, Episode 1 “And Then There Were 10”
Ben’s single most overpowered starting forms, Diamondhead is one of Ben 10‘s best aliens in general, let alone in the first series. Alongside Four Arms, Diamondhead was one of Ben’s go-to transformations, and for good reason. Being made of literal diamonds made him incredibly durable, able to regenerate from most injuries that could hurt him by re-growing his crystalline structure on the fly. Offensively, Diamondhead could form his body into a variety of useful shapes, expel sharp diamonds from his hands like a cannon, or entrap his enemies with massive crystals that grew from the ground.
Diamondhead was comfortable in many environments, able to breathe underwater, shrug off extreme heat, or even the vacuum of space itself. Ben’s enemies always had a difficult time contending with his powerful options as Diamondhead, easily able to use his immense strength to go toe-to-toe with most aliens or simply trap them in solid crystal. It’s no wonder that a being made of the most durable material on Earth was one of the single most powerful and iconic aliens in the entirety of Ben 10.
