His appearance is his Alien Force look with his head visor up.
Tetrax is a battle-hardened bounty hunter with a strong desire to do what is right. This is partly due to his involvement in the destruction of his home planet, Petropia.
Tetrax claims that he used to be a being who cared about no one but himself and that is what led him to become a mercenary. It was only after Vilgax destroyed Petropia that he realized the effect his actions had on his own people.
Powers and Abilities
Being a Petrosapien, Tetrax's body is made of organic, nearly indestructible diamond-like crystals that can refract light, causing him to be immune to most energy weapons.
Tetrax has a limited ability to regrow lost limbs, as well as alter his own physical constitution, making him able to do things such as fire crystal fragment as projectiles, turn his hands into blades, create structures out of his crystals, etc. He's shown to be much less skilled with his powers than Diamond Man (Tony's newest alien).
In addition to his natural powers, Tetrax is an experienced bounty hunter with excellent fighting and strategy skills. Tetrax is also shown to be highly knowledgeable in regards to various advanced technologies, including a great understand of how the Omnitrix works.
Tetrax was sent down to Earth by his employer, unknown, to take the Ultimatrix from Tony and to give it to him. Tony scans Tetrax and gains the powers of Tetrax and is defeated by the new Ultimatrix user.
- Tetrax says this phrase which is the name of the episode: "Hand over the Ultimatrix, boy."