Alien Species

Vaxasaurians are a race of humanoid dinosaur-like aliens from the planet Terradino.[1]



In their base size, Vaxasaurians resemble humanoid dinosaurs with four-fingered ape-like hands, three-toed elephant-like feet, white almost Human-like teeth with some fangs, eyes that either lack pupils or have cat-like pupils, and eyebrow-like extensions on their foreheads.

Male Vaxasaurians have tan, brown, beige, dark green or gray skin with their underbellies, the front side of their necks, and sometimes the sides of their arms that face the body being lighter-colored. Certain males have more defined plating, rugged chins, and horns sticking out from the sides of their head that curve downwards.

Females have medium red skin with stripes around their body that are a darker shade, slightly darker underbellies, and slimmer chins. They also appear to have feminine mammalian traits.

When at full size, Vaxasaurians gain Stegosauride plates on their backs and thagomizers on the tail. Three plates on their shoulders separate and grow alongside the plates on the forearms. A small triangular extension on the top chest plate forms on the bottom while the bottom sides stretch down and curve towards the center, ending at a point. The legs also seem to become slightly longer.


Much like Earth dinosaurs, Vaxasaurians reproduce by laying eggs.


Vaxasaurians are omnivorous.[2]

Vaxasaurians are preyed on by Kaosseffexx Ultimasaurias, especially since they are unable to lift them for long periods of time and can be trapped by their webbing.

Powers and abilities

Vaxasaurians are skilled in gladiatorial combat and possess tremendous superhuman strength for their size, allowing them to throw objects into near-orbit, bench press a pickup truck,[1] lift a To'kustar even in their base height,[3] and fight on-par with other beings around their size, such as Tiny's Species, Acrosians, Detrovites, Appoplexians, and Perplexahedron guards. Technically speaking, they are physically stronger than Methanosians and Crystalsapiens.[4]

Vaxasaurians have the power to increase or decrease their own body size and mass using dimensional displacement.[4] They can grow bigger to nearly 60 feet (~ 18.288 m)[1][5][6] at will, increasing their natural strength and making their dinosaurian features pronounced. They can sometimes generate their Stegosauride features without having to change their size. They can even shrink down to about 10 feet (~ 3.04 m).[4]

A Vaxasaurian's thick hide makes them durable against most attacks. For Omni-Kix and Omni-Naut Vaxasaurians, their natural durability is increased thanks to their respective armors.

Vaxasaurians are quite agile for their size, being able to perform tackle slides and evade attacks while jumping.

Certain Vaxasaurians seem to have naturally occurring weapons on the ends of their tails that resemble a plethora of medieval weaponry including maces, swords, war hammers, and battle axes.

Vaxasaurians can produce shockwaves by either clapping their hands together[7] or slamming their tails (especially those with weapons) against the ground. These shockwaves can blow away those affected within its vicinity.

Due to the alterations Kevin Levin has made to the Antitrix, Humungoraptor is more powerful than ordinary Vaxasaurian. He also has natural armor akin to an Evolved Vaxasaurian's, sharp claws and teeth, and can fire powerful energy beams from his mouth.

Omni-Kix Vaxasaurians can absorb energy through their back spines with every impact or attack they make. Once enough energy has been gathered, they can fire powerful green energy blasts from their mouths.

Regular Vaxasaurians can temporarily survive in the vacuum of space without any special equipment. However, Omni-Naut Vaxasaurians can easily survive in space thanks to their armor.

Besides space survivability, Omni-Naut Vaxasaurians can breathe underwater thanks to their armor[8] and fly through the use of their jetpacks.

When under the effects of an Earth cold, Vaxasaurians can accidentally sneeze out sprays of slimy snot from their mouths.


A Vaxasaurian's large size makes them very slow, unable to fit in tight places, and an easy target for enemies.

Vaxasaurians are primarily built for terrestrial land, meaning they require oxygen to survive. Consequently, they are unable to breathe underwater without Omni-Naut armor or some other form of equipment.

Correlating with their need for oxygen, Vaxasaurians are limited to holding their breath while in space.

Vaxasaurians can be harmed by electricity, such as an Amperi's attacks. They can also be harmed by fire even when at full size, such as the attacks of either a Methanosian or a Pyronite.

There is a clear limit to a Vaxasaurian's natural durability, as they can feel pain from an Aerophibian's neuroshock blasts and having their tails bitten by Bashmouth's Species.

Vaxasaurians can be trapped in webbing, such as that generated by a Kaosseffexx Ultimasauria or an Evolved Arachnichimp.

Despite their enhanced strength, Vaxasaurians are unable to lift anything bigger than a Kaosseffexx Ultimasauria. Technically speaking, they are physically weaker than evolved Vaxasaurians, Atasians, Chimera Sui Generi, Pallorfangs, and Tetramands.[4]

Vaxasaurians can be easily overpowered by a Celestialsapien's telekinesis.

Vaxasaurians can be lifted by a species with as much strength as Prypiatosian-Bs and Trombipulor's Species.

A Vaxasaurian's tail weapon can accidentally cause collateral damage and make them injure themselves.

Vaxasaurians are unable to create shockwaves if they slam their tails on soft surfaces such as mud.

Omni-Naut Vaxasaurians can be knocked out of the sky if their jetpacks take enough damage.

If under the effects of an Earth cold, a Vaxasaurian's natural strength and stamina are severely reduced.

Culture and society

At first glance, Terradino is the perfect candidate for a dream vacation brochure. A beautiful mountainous, temperate world, Terradino is home to a vast and varied number of animalistic alien species, many creatures great and small. Tragically, the inhabitants of Terradino have not evolved to live here together peacefully. Warring factions in every group constantly seek to wrench control of society for themselves.

Fortunately, the Vaxasaurians have been able to temporarily restore order through their sheer physical superiority.[9] However, there are still worries that the violence and chaos will return and destroy their beautiful planet once and for all.[6]

The Vaxasaurians appear to have better relations with the Appoplexians due to their prowess in gladiatorial combat. Though they are physically stronger, the Vaxasaurians display good sportsmanship.


Vaxasaurians are more technologically advanced than Humans, as they can travel through space and engage with other species.[2]


Vaxasaurians can occasionally be seen in clothing. The attire can include caveman-like loincloths, stone-based accessories, and/or bones and skulls of other species.

Like Humans, a Vaxasaurian can develop a need for glasses.

Notable members

  • Humungousaur: An Omnitrix transformation used by Ben Tennyson
    • Dyno Mighty: An alternate version of Humungousaur used by the Ben Tennyson of Dimension 23.
    • Humungousaur (Ben 10 Franklin): An alternate version of Humungousaur used by the Ben 10 Franklin version of Benjamin Franklin.
    • Negative Humungousaur: An alternate version of Humungousaur used by Albedo.
    • Skateasaurus: An alternate version of Humungousaur used by Timothy.
  • Hugh: A Vaxasaurian actor who played Humungousaur in Albedo's stage play.
  • Suemungousaur: A female Vaxasaurian criminal
  • Claymore: A Vaxasaurian gladiator and the champion of Terradino.
  • Basher: A Vaxasaurian gladiator
  • Grille: A Vaxasaurian gladiator
  • Other Vaxasaurians include an unnamed announcer.


  • Humungoraptor: A mutant hybrid equivalent of Humungousaur used by an alternate Kevin 11,000.
  • Ultimate Kevin: 17-year-old Kevin Levin of the Prime Timeline transformed into an amalgamation of every alien available in the Ultimatrix prior to traveling to the Forge of Creation, including Humungousaur.
  • Gwen Tennyson: The Prime Timeline's Gwen Tennyson was temporarily transformed into a Vaxasaurian due to an Ultimatrix malfunction.
  • Glitch: Glitch has reconfigured his vehicle form when interacting with Humungousaur.
  • Azmuth: The Prime Timeline's Azmuth transformed into Humungousaur while using the Omnitrix.
  • Alpha Nanite: By copying the Ultimatrix, the Alpha Nanite transformed into an E.V.O. version of a Vaxasaurian.
  • Plant Clone: A Plant Clone of Ben Tennyson transformed into Humungousaur after stealing the Ultimatrix.
  • Bioids: The Prime Timeline's Vilgax transformed his Bioid army into copies of Humungousaur by linking them with the Omnitrix.
  • Liam: Liam was temporarily mutated into a Vaxasaurian due to an Omnitrix malfunction.
  • Fourmungousaur: A Biomnitrix transformation comprised of Vaxasaurian and Tetramand DNA.
  • Humungoopsaur: A Biomnitrix transformation comprised of Vaxasaurian and Polymorph DNA.


When the Appoplexians visited Terradino, the best warriors from both races participated in gladiatorial combat. Claymore, Basher, and Grille represented Terradino, whereas Muck, Dario, and Swiftfoot represented Appoplexia. When the match was tied up, the champions of both planets, Claymore and Muck, faced each other. Though the Vaxasaurians emerged as the winner, they still showed sportsmanship with the Appoplexians.

A group of Vaxasaurians visited Arburia for a day at a beach only to cause trouble for the local Arburian Pelarotas. When the Pelerotas had enough of the Vaxasaurians' behavior, they fought each other until they found out that the Vaxasaurians' tails can help Pelerotas make a big splash. With this compromise, the Pelarotas allowed the Vaxasaurians to stay so they could help make big splashes.



  • The name Vaxasaurian comes from the Icelandic "vaxa", which means "to grow", and "sauria", which is a clade of lizards; it was first used on-screen by Albedo in the Omniverse episode "The Ultimate Heist".
  • Before making their debut in the reboot series, it was confirmed that the Omnitrix in that series contained Vaxasaurian DNA.[8] Therefore, Humungousaur was one of the countless aliens whose DNA pod was glimpsed in the episode "Innervasion Part 5: High Override" before being added to the active playlist for Season 3, replacing Wildvine.
  • It has originally stated that Vaxasaurians in the reboot continuity cannot alter their size. The statement was later refuted.[8]
  • An Omni-Kix Vaxasaurian's ability to fire green energy blasts from his mouth is a homage to Godzilla's atomic breath.
  • Although they are from different universes, a Vaxasaurian's physical strength is comparable to Metahumans such as Sasquatch. However, they are not as strong as the Hulk.[8]
  • Vaxasaurians do not hibernate.[2]


  1. 1.0 1.1 1.2 According to Humungousaur's bio card from Bandai's Ben 10: Alien Force toyline
  2. 2.0 2.1 2.2 According to Derrick J. Wyatt
  3. According to Eugene Son
  4. 4.0 4.1 4.2 4.3 According to Dwayne McDuffie
  5. According to the Ben 10: Alien Force production bible
  6. 6.0 6.1 According to Ben 10 Alien Force: The Complete Guide
  7. According to Matt Wayne
  8. 8.0 8.1 8.2 8.3 According to Duncan Rouleau
  9. According to the Nintendo DS version of the video game Ben 10: Alien Force