This is the version of Diamondhead that appears on Earth-68, the universe owned by Dioga beta. Diamondhead is the Omnitrix's DNA sample of a Petrosapien from the planet Petropia. His Ultimate form is Ultimate Diamondhead.
Crystalkinesis Weapon Manifestation Energy Refraction Energy Redirection Energy Absorption Enhanced Strength Enhanced Durability Aging Immunity Heat Resistance Space Survivability
Diamondhead is a silicon-based life form that is about 7 feet in height. His body is composed of durable green crystals. He sports 4 green crystal points on his back and has a sharp head.
In the episode Hunted (John Smith 10), Tetrax touches the Omnitrix, allowing for Diamondhead to be unlocked. He has since become one of John's most powerful aliens, easily able to defeat Vilgax.
Diamondhead is one of Ryder's original 10. Despite his size and weight, he can ride a motorcycle, though he weighs it down enough to slow down. This isn't a problem with the Tenn-Speed.