Rex Salazar at age fifteen.
Rex Salazar is a teenage (sixteen at the end of S1) amnesiac human-looking E.V.O. Like all of the E.V.O.s he has suffered a unique mutation, his being the ability to grow machines out of his body for virtually any occasion and then absorb them back into himself when done (this power is not unlimited he can only grow certain machines out of specific parts of his body and the only reason he can do this, as revealed in the episode Dark Passage it is because he was given the first batch of nanites instead of the ones that other people got). He can also cure some Evo's of their mutations in addition to using his Nanites to communicate and control nearby machines. Agent Six believes that there is something wrong with him (aside from the amnesia and Nanites) and believes that the reason why he's struggling with his nanites is because of his inability to control his emotions. Rex often vents his frustrations (such as the size of his room and the "all work and no play" outlook of Agent Six) by riding around the Evo habitat on his motor bike and breaking out of the base to go on "road trips" with Bobo Haha.
It is revealed by Van Kleiss in the first episode "The Day that Everything Changed" that he and Rex were both at the Nanite explosion. It is revealed in the episode "Frostbite" that if he absorbs too many Nanites he can't control them and they can take him over and possibly make him explode. It is also revealed in the episode, "Dark Passage" that Rex had an accident when he was young and that Dr. Rylander gave him the first batch of fully developed, fully programmed nanites to save him. Although some unexpected side effects came later. It was revealed that he has an older brother named Caesar(who he meets in the episode Mixed Signals and Caesar reveals that their parents, Rafael and Violetta- were sadly killed in the nanite explosion and Caesar joins Providence), and that it was Rex's powers that saved them from the Nanite Event explosion.
His main love interest, beloved sweetheart and girlfriend is the human-looking E.V.O. Circe, who possesses unusually strong hypersonic/sound abilities. She returns his strong romantic feelings.
E.V.O. Abilities and Powers[]
Rex has the ability to generate a total of nine different bio-menchanical machines from his body and can return to his human form when done. Previews of the show have suggested that damage to the machinery in battle does not effect his nervous system or body in any way. Rex can generate the following machines from his body:
| Name | Body Part | Special Power/Ability |
| Big Fat Sword (B.F.S.) | Arm | Sword's tip can turn into a chainsaw |
| Slam Cannon | Arm (also rests on shoulder) | Uses any available material as ammunition |
| Smackhands | Hands | Can rotate at high speeds to dig or pound enemies |
| Punkbusters | Feet | Can let Rex can leap for extreme distances |
| Boogie Pack | Back | Can shoot turbines attached to wires/Make him fly |
| Rex Ride | Legs (sat on when used) | Hovers and glides; can uncover front to reveal a metal battering ram |
| Whip | Back and Arm |
Can extend; is blue instead of orange like the rest of his weapons; first new weapon; can deliver an electric shock generated by backpack |
| Club | Hands | Shining blue Clubs/shoot energy blasts when spun then smashed together |
| Shield Gaunlets | Hands | creates circular energized shields from the back of the hands. Can also become a dome-shaped shield around himself and others. |
| Axe | Hands | Giant blue Axes;shining blue blades that can slice and slash through anything |
hover board feet can fly like his boggie pack faster then them
Personality and Characteristics[]
Rex is shown to have a externally overconfident personality, suggested by his bold remarks and inability to listen to Agent Six's orders during battle. In the initial preview, it is revealed by Dr. Holiday that he has insecurities about his capabilities. She states that his "machines fell apart" due to the fear of disapointing Agent Six. Rex refers to Six as "a nanny, just more Agro" (though apparently the agent himself despises the use of the term). He also admires Six's martial arts abilities and secretly looks up to him, hoping that one day he will teach Rex some of his own tricks.
He is very headstorng, stubborn and willfull, which he had inerited from his Mexican mother, Violetta. He is also quite good-hearted, tender, caring, selfless, considerate, tolerant, strong-willed, self-sacrificing, heroic, high-spirited, and desires to help people and save lives whenever he can.