Ben 10: Diamondhead

Diamondhead is a silicon-based life form. His body is composed of durable green crystals. He sports four green crystal shards on his back and has a sharp head.
In the original series, Diamondhead wears a uniform which is black on the right half and white on the left with a black patch on the left shoulder where the Omnitrix symbol is.

In Alien Force and Ultimate Alien, Diamondhead's torso is similar to Chromastone's, consisting of indigo crystal which has black lines and dots over it. There are now six crystal shards on his back instead of 4 and he now also sports two more on the front of his chest. He wears the Omnitrix/Ultimatrix symbol on his chest.

Gwen as Diamondhead has darker and shinier diamonds, thinner arms, a more rounded body, no shards on her back and a more square head. She wears a uniform like Ben's Diamondhead in original series, except it is half dark blue, half light blue. She wears the Omnitrix symbol on her left chest.

In Ben 10-Generator Rex: Heroes United, Diamondhead looks more real-world crystal-like due to being drawn in Generator Rex-style. He also has a blade on his elbow, similar to that of XLR8's.

In Ben 10: Omniverse, Diamondhead has clothing almost similar to the first series except that now instead of half black and half white, it is all black with one large green stripe down the middle up to his belt, and wears black pants. He has a green with white stripes belt on which he wears the Omnitrix symbol. Also Diamondhead no longer bears the crystals on his chest. The crystals on his back have grown in length also. His jaw is also larger. He also wears black shoes with green on the bottom.

11-year old Diamondhead looks almost identical to the original, but the left side of his suit is missing the black patch around the Omnitrix symbol. His jaw is also larger too. His eyes are green and the Omnitrix is recolored.