List of Generator Rex characters

The following is list of characters that appear in the 2010 animated series Generator Rex.

Rex Salazar
Rex Salazar is a teenage (sixteen in Season 1) half-Argentinean, half-Mexican E.V.O born to a family of scientists. Unlike other E.V.O.s, Rex can control his nanites at will, allowing him to appear human and cure other E.V.O.s of their mutations. He can also use his nanites to create various machines on his body and communicate with and manipulate technology. After being injected with the specialized Omega Nanite, he gains the ability to create stronger and more effective machinery with unique properties. He also becomes strong enough to cure animals of nanites and detect Breach's presence. His girlfriend is a siren-like E.V.O. named Circe, who originally worked for Van Kleiss, but defected after realizing that he desired Rex "alive" in body only. She then joins his E.V.O. gang in Hong Kong, China. According to Van Kleiss, he inherited his late mother Violetta's headstrong nature.
 * Voiced by: Daryl Sabara

After being sent six months into the future as a result of Breach's newfound time-traveling ability, Rex fights against Providence's new boss, the power-mad Black Knight, to stop her and the Consortium from attaining infinite godhood from the five nanites called "Meta Nanites" ("Master-Control Nanites"). He alone can fully control them in their purest state, as his late parents had secretly programmed them to fully work for him. He is now dating Circe, as their romantic relationship is revealed to be genuine in "Assault on Abysus". After the events of the finale, he enters a full romance with her, and is the only E.V.O. left to defend the world from further threats.

Agent Six

 * Voiced by: Wally Kurth

Agent Six is a senior Providence agent and Rex's handler, whose name comes from the fact he is the sixth most dangerous person on the planet. Because of his strict and by-the-book personality, Rex refers to him as a "nanny, just more aggro." He has brown eyes and wears a green suit with a black tie and black sunglasses. Over time, he falls in love with Dr. Rebecca Holiday, confessing his feelings for her in "A Family Holiday". Despite losing six years of his memory in "Six Minus Six.", he seemingly regains his feelings for her.

Bobo Haha

 * Voiced by: John DiMaggio

Bobo Haha is an E.V.O. chimp with the ability to speak, who is Rex's sidekick and friend. He wears an eye patch and fez. He claims that before he was turned into an E.V.O., he was a helper animal trained to entertain children at a hospital, whose owner was an eccentric philanthropist.

Dr. Rebecca Holiday
Dr. Rebecca Holiday is the lead scientist for Providence and expert in nanotechnology. Along with Agent Six, she is responsible for taking care of Rex and takes her job seriously, acting as a surrogate mother for him. Rex had a school boy crush on her until her age appropriate sister was cured. She also harbors a crush on Six, which he grows to reciprocate in "A Family Holiday" and starts to recall in "Riddle of the Sphinx" after losing his memories in "Six Minus Six."
 * Voiced by: Grey DeLisle

Noah Nixon

 * Voiced by: Fred Savage

Noah Nixon is a human and Rex's best friend. He is an agent sent by White Knight to befriend Rex and subtly influence his decisions to make him more compliant. Noah eventually reveals to Rex his status as a covert agent, and despite this they became friends on open terms. His girlfriend is his high school classmate Claire Bowman.

White Knight

 * Voiced by: J. K. Simmons

White Knight is the leader of Providence and the only known nanite-free being on the planet. He almost always stays in his office, communicating his orders through two-way screens. He has a Mysophobia-like fear of nanites, as he does not want to touch or be near E.V.O.s out of fear they will infect him with nanites. Because of this, in the third season he dons a nanite-free battle suit. In the five years after the Event, he had short pale brown hair and was a skilled agent for Providence working under Dr. Fell as well as Six's closest partner.

Van Kleiss
Van Kleiss is the primary antagonist of the show, a British scientist who specializes in biointerface and biomechanical integration. He expresses insanity to mask his evil and ambitious nature until he can fulfill his goal of absorbing the five Meta Nanites to attain godly abilities. In the past, he was responsible for the deaths of Cesar and Rex's parents, Rafael and Violetta, by trapping them inside as the nanite reactor exploded. He appears to know about Rex and his forgotten past, and that Rex's older brother Cesar seemingly caused the nanite incident five years prior. He saw the Nanite Event as the dawn of a new golden age for evolved humankind, and seeks to create a planet populated by E.V.O.s. regardless of their weakness or frailties. Like Rex, he is able to control his nanites, but his mutation is unstable and requires a constant supply of fresh nanites for survival by extracting them from other E.V.O.s., who are petrified in the process. Upon acquiring Rex's batch of fully programmed original nanites, he gains the ability to create and control E.V.O.s, a mutation which becomes permanent if not cured by Rex in less than an hour. After Breach's portal-making ability is increased by the amp pack he made for her, he is sent to the ancient past, where he was present in the primitive eras of Egypt and met Emperor Septimus Severus of Ancient Rome. He managed to create an Egyptian E.V.O. called G'raan Set in a makeshift laboratory, then preserved himself in a hibernation chamber that stored his unstable nanites and ensured he was able to survive to the present. After being defeated, his golden gauntlet is destroyed and he is taken to Breach's pocket dimension of Greenville, Ohio.
 * Voiced by: Troy Baker

The Pack
The Pack is a group of E.V.O.s that serve Van Kleiss. Its known members include the following:

Biowulf

 * Voiced by: Troy Baker

Biowulf is a blue-armored, white-haired, werewolf-like E.V.O. with large claws, who is fiercely loyal to Van Kleiss, whom he calls "master." Owing to Van Kleiss' powers being limited to his native soil in early episodes, he initially acts as the Pack's de facto leader in the field.

Skalamander
Skalamander is a large humanoid lizard-like E.V.O. with crystal spikes growing out of his body and a crystal club growing out of his left arm.
 * Voiced by: John DiMaggio

ZAG-RS

 * Voiced by: Grey DeLisle

ZAG-RS is a sentient and autonomous, self-aware artificial intelligence/multi-agent system who aims to destroy the nanite infestation of Earth, which will destroy all of humanity in the process. Its origin and motives are initially a mystery, but it is able to exert control over nanites at very short ranges. It makes several attempts to achieve its goal, but Rex stops it each time. Its feminine voice was modeled after the deceased Mexican scientist Violetta Salazar's, as its inventor, a teenage Dr. Cesar Salazar, wanted it to have a voice that represented safety, protection and caring; the feelings of a loving mother.

Agent Weaver

 * Voiced by: Troy Baker

Agent Weaver is a former member of Providence stationed at the arctic "Paradise" base, where he was the chief technician. He and his crew are later revealed to be traitors reactivating and selling nanites to Van Kleiss.

Hunter Cain

 * Voiced by: John Cena (1st Time), John DiMaggio (2nd Time)

Hunter Cain is an E.V.O. hunter who despises all E.V.O.s, having previously become insane after his wife became an E.V.O. He uses a weapon loaded with special bullets that forces Nanites to self-destruct, instantly vaporizing E.V.O.s.

NoFace

 * Voiced by: Fred Tatasciore

NoFace is a supremely powerful and vengeful faceless E.V.O. with the ability to communicate with intelligent E.V.O.s and control less intelligent ones. During the nanite event, the Gulf Stream funneled a huge amount of active nanites into the city of Kyiv, Ukraine, transforming most of its inhabitants into powerful E.V.O.s, including their current leader, NoFace.

Quarry

 * Voiced by: Mark Hamill

Quarry is an E.V.O. crime lord made of rock. He hunts down and forces E.V.O.s such as Tuck, Skwydd, and Cricket to work for him through having gathered a massive criminal empire. In "Rabble", he learns of Rex's return from his enforcer Knuckles after Rex drains him of his nanites, forcing Quarry to dispose of him. He reappears in "Hard Target", when Breach releases him, but he ends up being taken to Abysus and tortured by Van Kleiss. His final appearance is in "Remote Control", where Van Kleiss mind-controls Sqwydd, Tuck and Cricket to attack Rex. He is ultimately defeated by Rex and his body is blown apart, leaving only his head behind.

Gatlocke
Gatlocke is a British cyborg and the a leader of a group of modern-day pirates known as "The Anarchists", who debut in "Badlands." He eventually makes his second and final appearance in "Enemies Mine", where he tries to take out Rex once and for all by teaming up with Hunter Cain, NoFace and Valve. Their fates are unknown since they were trapped inside a shield made by Rex's surplus nanites at the Purgatory Base.
 * Voiced by: Greg Ellis

Black Knight

 * Voiced by: Jennifer Hale

Black Knight is the next leader of Providence after White Knight rebels against his superiors in the Consortium. After taking over Providence, she starts to run things differently from how White Knight had, as she believes in controlling the incurable E.V.O.s rather than trying to cure them. She secretly attempts to become a almighty goddess by attaining all five Meta Nanites for herself, turning on her own superiors in the process. She is eventually captured off-screen.

Valve

 * Voiced by: Maurice LaMarche

Valve is a samurai-styled biker and a dealer of an altered form of nanites which can link a person to technology. He makes his second and final appearance in "Enemies Mine", where he tries to take out Rex once and for all by aligning himself with Hunter Cain, NoFace and Gatlocke. Their fates are unknown since they were trapped inside a shield made by Rex's surplus nanites at the Purgatory Base.

Gharun Set
Technically the first E.V.O. created, Gharun Set was an ancient Egyptian E.V.O. created by Van Kleiss after Breach's powers sent him back in time to ancient Egypt. After creating a nanite production chamber, which Set calls the "engines of life", Van Kleiss infused them into Gharun Set, changing his appearance into a dog-headed mummy-like humanoid with an eye in the center of his chest.
 * Voiced by: Hakeem Kae-Kazim

The Consortium
The Consortium is a powerful organization which supports Providence and are the superiors of Black Knight. Little is known about them, but they seem to provide funding for Providence and the Nanite Project. In six years, they managed to merge with four of the five Meta Nanites, turning into biomechanical robots with powers such as teleportation, pyrokinesis, cryokinesis, and electromagnetic-controlling abilities.

Reddick

 * Voiced by: Robin Atkin Downes

Reddick is a real estate agent and construction associate who is a member of the Consortium. When merged with a Meta-Nanite, he was transformed into a giant gray robotic E.V.O. with the ability to control gravity and fly.

Roswell

 * Voiced by: Troy Baker

Roswell is a southern businessman and oil and mineral associate who is a member of the Consortium. When merged with the Meta-Nanite, he was transformed into an E.V.O. with red and blue armor and the ability to control fire and ice.

Sir Anthony Haden-Scott

 * Voiced by: Robin Atkin Downes

Sir Anthony Haden-Scott is a British worldwide media associate and a member of the Consortium. When merged with the Meta-Nanite, he was transformed into an E.V.O. with dark gray armor with orange lightning strikes on it and the ability to manipulate matter and energy and fly.

Xanubian
Xanubian is an African American arms dealer and shipping industry associate who is a member of the Consortium. When merged with a Meta-Nanite, he was transformed into a tall and thin robotic E.V.O with green armor and the ability to manipulate time and space. Unlike the others, he is mute, although Roswell calls him a chatterbox.

Vostok

 * Voiced by: John DiMaggio

Vostok was a black market financier and KGB operative who is a member of the Consortium. He was with the Consortium when Black Knight began her plans to restart the Nanite project. Vostok had some doubts about her plot, and so she killed him when they were alone, telling the other Consortium members that the enemy was responsible for Vostok's death.

Alpha

 * Voiced by: Michael Emerson

Alpha was created by Caesar to control other nanites as a sentient being, with power equivalent to the Omega Nanite/fifth Meta Nanite within Rex's body. Since his energy/nanite body was unsustainable. he tried to make mechanical bodies to sustain himself. But after this plan failed, he tried to use organic beings as hosts, resulting in Ben entering the world of Generator Rex and causing the events of Heroes United. He is ultimately taken back to the Null Void by Ben Tennyson (in the form of Upchuck) and escapes his metallic prison as the Omega Nanite is re-injected inside Rex.

Diane Farrah
Diane Farrah is a newswoman who hosts a news program called "Ultimate Exposure". She appears regularly where Providence fights EV.O.s, as a hostess of her program or when she is interviewing people involved with E.V.O.s.
 * Voiced by: Grey DeLisle

Breach
Breach is a four-armed human E.V.O. Using her larger arms, Breach can tear open space and time, creating red wormholes which turn golden after her spatial abilities were boosted by Van Kleiss' amp pack. Her portals seemingly have a plane, as those who go through them can stand within the portal without having to step out on either of the linked locations. Her own personal place is Greenville, Ohio, which she absorbed into a portal and keeps as her own dollhouse to stay sane. It is where she takes Biowulf, Skalamander and Van Kleiss as Rex uses the God Code to cure all EV.O.s.
 * Voiced by: Hynden Walch

Circe
Circe is a dark-haired humanoid teenage E.V.O. with sound-based abilities and the ability to lure fellow E.V.O.s like a siren's song. She debuts in the third episode, "Beyond the Sea", where she and Rex begin to feel a powerful connection form between them, though she still chose the Pack over staying with Rex, as she did not trust Providence's methods. She meets Rex again during her first mission as Van Kleiss' subordinate in "Leader of the Pack", where she hesitantly knocks Rex unconscious and imprisons him, despite being reluctant to resort to hurting him to help Van Kleiss.
 * Voiced by: Tara Sands

A few weeks after the unexpected demise of Van Kleiss in "Dark Passage", in "What Lies Beneath", she calls Rex for his help in dealing with Abysus, as Van Kleiss's link with the unstable nanites was lost and is causing it to crumble. After Rex learns that she plans to return Van Kleiss to life, she tries to reassure him that she needs him as much she needs Van Kleiss. She is nearly swept away by the unstable nanite goop, but after being saved and regaining consciousness in Rex's arms, she says that she is happy to see him. Despite thanking him for saving her life, she refuses to leave Van Kleiss as it keeps things interesting.

Her second and final mission with the Pack is in the Bug Jar when she discovers, to her horror, that Van Kleiss is more interested in what Rex's body would give him and does not care about what could happen to his psyche. After this, she leaves to join Rex's old friends in Hong Kong, China and develops a close friendship with Sqywdd, which she assures Rex is platonic. She also starts doing her hair and nails with Cricket every weekend.

Half a year into the future, in "Assault on Abysus", she is asked to help bring Rex throughout Abysus to procure a Meta Nanite before Black Knight can, telling him that there is nothing between them except the mission. Ultimately, she confesses her true feelings for her and kisses him before letting herself be taken by New Providence to save him. In "Mind Games", the shapeshifting E.V.O. John Scarecrow, a former partner-in-crime of Rex, takes on her form to mess with Rex's emotions.

In "Endgame, Part 2", after being cured along with the rest of humanity, she embraces Rex and assures him she is "normal but okay" and jokingly says he had "put himself out of a job" by curing the world. It is later confirmed that they are dating as Rex continues to act as the planet's defender.

Claire Bowman
Claire is a girl that Noah likes since she is the most popular girl in high school. She is best friends with a clumsy teenage girl named Annie. She debuts in "Operation: Wingman", where she agrees to go to the prom with Noah if he finds Annie a date. She also appears in "Haunted", in which she meets Rex's elder brother Cesar and is impressed with his intelligence.
 * Voiced by: Danica McKellar

In "Guy Vs. Guy", she goes on another date with Noah while he and Rex were going all-out on a prank war that ended up endangering the entire city when Bobo Haha got involved. She makes her final appearance in "Hermanos," where she and Annie go with Noah and Rex to Argentina to see the ancestral ranch that Rex inherited upon the death of his father Rafael, as a birthday present from Noah.

Annie
A good friend of Claire Bowman, who struggled to find a date for junior prom because of her clumsiness. Noah persuades Rex to come to the prom as his "wingman" and take Annie out as well. Since then, Annie has double dated with Rex several times. At the end of "Hermanos", Rex states that she, Claire, and Noah are his true companions and he considers them as his family as much as Six, Bobo and Dr. Holiday are.
 * Voiced by: Felicia Day

Rex's Old E.V.O. Street Gang
An E.V.O. street gang that has lived in Hong Kong, China since the Nanite Event. It is later revealed that when he was younger, Rex was the gang's leader before he lost his memory and joined Providence after Agent Six found him. There were others but had successfully been cured by Rex.

Tuck
Tuck is a red-eyed mummy-like E.V.O. who befriended a young Rex in Hong Kong, China, in the five years after the Nanite Event. He is best friends with Sqywdd and Cricket, and followed Rex as their leader even when encountering the shapeshifting E.V.O. John Scarecrow during their adventures.
 * Voiced by: Dante Basco

Skwydd
Skwydd, originally named Walter, is a humanoid squid E.V.O. who is serious, giving Rex serious/obvious answers when he jokes around. He is also shown to be moody and stoic, something that Rex jokes about. Skwydd has an interest in entertaining people as a freak show act.
 * Voiced by: Jason Marsden

In "Hard Target", Rex assumes that he and Circe are dating, but is relieved after he assures Rex that they are just friends. In "Remote Control", he ends up under Quarry's control after being collared by New Providence, but is ultimately cured in "Endgame, Part 2" and starts going by his real name "Walter" again.

Cricket
Cricket is a cricket-like human E.V.O. who is the only female member of Rex's street gang. She becomes good friends with fellow E.V.O. Circe, having another girl to "even out the boy-girl ratio" and do her hair and nails with every weekend. She is ultimately cured by Rex's nanite-powered godly abilities in "Endgame, Part 2."
 * Voiced by: Vyvan Pham

Dr. Rafael Salazar
Voiced by: Carlos Alazraqui
 * Dr. Rafael Salazar was the Argentinean scientist father of Cesar and Rex from Buenos Aires, who had worked on the original Nanite Project five to six years ago with his lovely yet headstrong Mexican wife Violetta and their teenage son Cesar. After settling down in Geneva,Switzerland, he became a father to his youngest son, Rex.


 * About one decade later, he, his wife, and Cesar began work on the Nanite Project with fellow international scientists Dr. Gabriel Rylander, Dr. Peter Meecham and Van Kleiss, in Abysus, United States, at the behest of the Consortium. Unfortunately, he was killed alongside Violetta due to Van Kleiss trapping him inside the exploding nanite reactor as the incomplete nanites scattered across the Earth. His office remained intact after the incident, in which a ten-year-old Rex had drawn pictures and, six years later as a teenager, recovered a photograph of his preteen self and his father in "Assault from Abysus". Cesar also possesses a picture of his own teenage self and a younger Rex with him.


 * His family has a ranch in a rural area of Argentina, which his sons inherit upon his death, as seen in "Hermanos." Over the next six years, it had been under the legal guardianship of a large humanoid bull E.V.O. named Derango until he is defeated by Rex and his friends Noah, Annie and Claire, freeing his family's rancho and the fellow villagers from his control.

Dr. Violet Salazar
Voiced by: Grey DeLisle
 * Dr. Violet Salazar was the late Mexican wife of Argentinean scientist Dr. Rafael Salazar, who eventually married him; they had two sons, Cesar and Rex. She was from Mexico City, Mexico, where she, Rafael, and their young sons spent their summers at a local town run by a woman they considered an abuela regardless of blood ties, where a young Rex had befriended Frederico. She traveled all over the world with Rafael and Cesar, but settled down after giving birth to Rex in Geneva, Switzerland. At her husband's family's ancestral rancho in Argentina, she had held the video camera as Rafael was telling a young Rex how the nanites would eventually change the world for the better, and that he would be there to see it. She had asked Cesar to stop working fir a bit and hold the camera for her. When her husband had jump-started the reactor, she panicked and pleaded her young son to run for safety as she and Rafael her trapped by Van Kleiss.


 * She agreed to work on the Nanite Project with Rafael and Cesar's help in Abysus, United States, alongside fellow scientists Dr. Gabriel Rylander whom she had chosen to be Rex's godfather, Dr. Peter Meechum, and Van Kleiss. She died alongside Rafael after Van Kleiss trapped them inside the lab harboring the unstable nanite reactor. A teenage Cesar, ten-year-old Rex, Dr. Meechum, and Dr. Rylander managed to escape as hundreds of uncontrollable and underdeveloped nanites spread throughout the world and bonded with human and animal physiology in an event known as the Nanite Event. Because she was a motherly symbol of safety, caring and protection, her eldest son modeled the autonomous artificial intelligence Zag-RS' voice after hers. According to Van Kleiss, she was quite headstrong, like Rex. Her middle and maiden name is unknown.

Dr. Cesar Salazar

 * Voiced by: Freddy Rodriguez
 * Dr. Cesar Salazar is Rex's long-lost Argentinian/Mexican older brother in his late twenties and one of the surviving scientists of the Nanite Project alongside Dr. Peter Meecham, Van Kleiss. and Dr. Gabriel Rylander, who he managed to partially return to life. Alongside his parents, he secretly programmed the five Meta Nanites to obey only Rex, with the fifth and strongest one being injected into fifteen-year-old Rex by Dr. Rylander, who perished alongside Van Kleiss one year ago.


 * In the six months after Rex's sudden "disappearance", Cesar had kept his cover in giving the all-powerful God Code to his younger brother, even if it meant appearing as an unfeeling enemy in his eyes. It is later revealed he was merely playing along with the Consortium and Black Knight's schemes for world domination for Rex to acquire five the Meta Nanites' abilities at their fullest.


 * He possesses a photograph of a ten-year-old Rex and his younger teenage self with their late Argentinean father, Rafael. He is starting to work on a brand-new project with surviving scientists Dr. Peter Meechum and the still-incorporeal Dr. Gabriel Rylander, sure that his parents would be proud of him and Rex.

Benjamin Kirby Tennyson

 * Voiced by: Yuri Lowenthal
 * Ben is a sixteen-year-old teenager who wields the Ultimatrix, formerly the Omnitrix. In Heroes United, he arrives in Rex's world through a space-time rift in the Null Void and helps him battle Alpha. Ultimately, he returns Alpha to its interdimensional prison in the form of Upchuck.

Humungousaur

 * Voiced by: Dee Bradley Baker

Humungousaur is a Vaxasaurian, a large brown dinosaur-like alien that possesses incredible strength and can grow in size and become stronger.

Diamondhead

 * Voiced by: Dee Bradley Baker

Diamondhead is a Petrosapien, an alien with crystalline features that can grow and manipulate diamond-hard crystals at will. He is also able to reshape his limbs, such as turning his arm into a sharp blade, as well as firing crystal projectiles.

Lodestar

 * Voiced by: Dee Bradley Baker

Lodestar is a Biot-savartian, an alien with a floating metal head in between two sharp shoulders that act as a magnetic field. He has crab-like claws and a body that is mainly black, with yellow feet, hands, shoulders and chest. He possesses the power to control magnetic forces and manipulate metals and other magnetic objects.

Rath

 * Voiced by: John DiMaggio

Rath is an Appoplexian, a tiger-like alien with high arrogance and aggressiveness. He can retract two short blades from behind his knuckles to enhance his punches.

Big Chill

 * Voiced by: Dee Bradley Baker

Big Chill is a Necrofriggian, an asexual humanoid moth-like alien whose wings and antenna can fold up into a hooded robe. He has a black body with blue and white spots which resemble ice chunks on his limbs. He has the ability to exhale freezing vapor that can encase his targets in ice and the ability to become intangible, which he can combine to freeze objects he passes through.

Cannonbolt

 * Voiced by: Dee Bradley Baker

Cannonbolt is an Arburian Pelarota, a round alien with a hard shell who can curl into a ball to move quickly. His body is mostly colored white with black stripes.

XLR8

 * Voiced by: Yuri Lowenthal

XLR8 is a Kineceleran from the planet Kinet who has the ability to move at high speeds. He has a black body with a blue striped tail and a spiked helmet with a blue visor; as well, he has wheels on his feet.

Four Arms

 * Voiced by: Dee Bradley Baker

Four Arms is a Tetramand, a four-armed, red alien with superhuman strength. He wears gold gauntlets on his arms and long black pants with a gold belt.

Shocksquatch

 * Voiced by: David Kaye

Shocksquatch is a Gimlinopithecus from the planet Pattersonea. He resembles a yeti and can manipulate and emit electricity.

Upgrade

 * Voiced by: Yuri Lowenthal

Upgrade is a Galvanic Mechamorph, a humanoid alien with black skin and green mechanical prints throughout his body. He possesses the ability to manipulate, possess, and enhance technology.

Upchuck

 * Voiced by: Dee Bradley Baker

Upchuck is a Gourmand, a reptilian-like being who can digest and then expel energy and solid matter. Ben uses him to carry Alpha's compressed sphere into the Null Void.

Gwen Tennyson

 * Voiced by: Ashley Johnson

Ben's cousin, who possesses powerful magic abilities, in part due to her alien Anodite heritage. She accompanies Ben and Kevin to Japan, where Ben makes a commercial for Mr. Smoothie. Upon meeting Rex, she is seemingly impressed by what Ben tells her about his abilities. She later opens a portal to Rex's universe for him and Bobo to return home.

Max Tennyson

 * Voiced by: Paul Eiding

Max Tennyson is the paternal grandfather of Ben and Gwen. Despite his age, he has shown on multiple occasions to be a formidable fighter. He was once in the United States Army, an astronaut program, and was a Plumber. Before Ben got the Omnitrix, Max tried to keep the Plumbers and the aliens a secret from his family because he wanted to protect them. However, his plan failed when the Omnitrix and Vilgax came to Earth.

Kevin Levin

 * Voiced by: Greg Cipes

Kevin Levin is Ben's friend, a reformed criminal with the ability to absorb the properties of matter, energy, and DNA through touch. He is able to adapt solid matter to his body and make it "armor" that protects him and enhances his strength. In addition, he is capable of transforming his hands into any weapon with the absorbed material.

Beverly Holiday

 * Voiced by: Jennifer Stone

Beverly Holiday is Dr. Holiday's younger sister, who turned into a spider-like E.V.O. when she was thirteen. She is kept in "The Hold", a containment area meant to hold the most dangerous creatures of the Petting Zoo, and Dr. Holiday has been trying to find a cure ever since.

Peter Meechum

 * Voiced by: Jeff Bennett, Wil Wheaton

Peter Meechum is a man who was turned into a zombie-like E.V.O. with an exposed human body and a blob-shaped head on top, with his actual head in the other head's mouth. In this form, he had the ability to turn anyone he touches that have nanites in them into zombie-like creatures that obey him.

Dr. Gabriel Rylander

 * Voiced by: Brent Spiner

Dr. Gabriel Rylander is a scientist who worked on the Nanite Project with Rex's parents and other scientists. He was one of the original Nanite Project scientists, and wanted to change the Earth by using nanites to end starvation and disease. After an accident, he took part in Rex's nanite treatment.

Kenwyn Jones

 * Voiced by: Rutina Wesley

Kenwyn Jones is a former Providence cadet.

Providence was responsible for saving her family, and she later joined them because she wanted to repay her debt to them. The experience seemed to have a profound effect on her, causing her to take her training seriously.

The Six
The Six are a group of mercenaries consisting of the six most dangerous people on Earth; Six was one of them. Each member's name goes by how dangerous they are. As noted by Six, the ranking focuses on how dangerous they are, which in turn is determined by skill level and personality.

One

 * Voiced by: Frank Welker

One was the most dangerous man on the planet and the leader of the Six.

Dos

 * Voiced by: Carlos Alazraqui

Dos is an elderly Spanish gentleman and the second most dangerous man on Earth.

Trey

 * Voiced by: Jim Cummings

Trey is a large man with a Cajun accent who is the third most dangerous man on Earth. He is physically the strongest of The Six.

IV

 * Voiced by: Frank Welker

IV (pronounced like Ivy) is a mummy-like mercenary who is the fourth most dangerous man on Earth. He has bandages covering his body that he uses as weapons and is seemingly able to control. He can use them to bind opponents and aid himself.

Five

 * Voiced by: Olivia d'Abo

Five is an English rocker girl with pink hair and a Cockney accent, who is the fifth most dangerous person on Earth.

Fitzy Feakins

 * Voiced by: Tom Kenny

Fitzy Feakins is a human E.V.O. who is urgently wanted by Providence for his E.V.O. powers.