Tetrax Shard

Tetrax Shard, dubbed "Hoverboard" in his first appearance for his namesake flying device, is a Petrosapien mercenary, hired by Vilgax in the episode Hunted to take the Omnitrix from Ben. He has nearly impenetrable gray armor, a black helmet with a small, green triangle (presumably for sight) on it, and carries a large rifle. His Petrosapien physiology can manifest through the armor, allowing him to use his powers without removing it. Unlike the other hunters, Tetrax is allied against Vilgax. Upon first discovering that Ben has the Omnitrix, he laments the fact that out of the planet's six billion inhabitants it would end up on the wrist of a child. He also berates Ben's lack of strategy in regards to its use. After helping Ben to defeat the other hunters, during which Ben learns to use the Omnitrix strategically, he decides that the Omnitrix is in good hands, allowing it to remain with Ben. He also gives Ben his hoverboard, saying that it might come in handy. Ben uses it several times throughout the series. In Ben 10: Secret of The Omnitrix, the hoverboard is melted in a vat of nuclear waste, but Ben is given a replacement.

Personality
Tetrax is a battle-harden 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 lead him to become a mercenary. It is only after Vilgax destroyed his home that he realized the effect his actions had on his own people. That experience made Tetrax into the heroic Omnitrix Guardian he became. He helps Ben become a better hero, teaching him to use the Omnitrix wisely (Ben later repays him by reviving Petropia's people). He also deeply despises Vilgax due to their history.

Power and Abilities
Being a Petrosapien, Tetrax possesses abilities same as Diamondhead's: his body is made of organic, nearly indestructible, diamond-like crystals who can refract light, causing him to be immune to most laser and energy weapon.

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 of this crystals, etc. He's shown to be much more skilled with his powers than Diamondhead.

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 knowledge in regards to various advanced technologies, including a great understand of how the Omnitrix works. In Ben 10: Destroy All Aliens, he was even able to reprogram the Omnitrix. Tetrax is equipped with various devices and weapons, such as an hoverboard, his own personal ship and a sonic device.