Onyx was created on Earth and was shipped to Homeworld to work as a miner. When the war began Onyx chose no side but wished to visit Earth. He was permitted to explore Earth but kill any Crystal Gems if seen. At the end of the war he left for Homeworld, still deciding to be neutral.
When the second war started he fought both sides when he saw fit. He became enemies with Gems such as Jasper, Amethyst, Ruby and Yellow Diamond. But he also became friends with Gems like Rose, Emerald, Obsidian and Tourmaline. He decided to live on Earth after the second war, taking up residence in Quartz.
Onyx's gemstone is located on his chest, right underneath his neck. His gem is oval in shape and is black. His hair is dark grey and it covers his right eye. His skin is a lighter shade of grey. His uniform is a dark silver shirt without sleeves, with a yellow star and diamond either side of his stomach. His pants and shoes are black, his pants with a small squared off zigzag pattern.
He is the tallest out of him, Emerald and Pyrite. He is almost as tall as Garnet.
"Well... He is a little... Blank"
Onyx has a very blank personality. He never cracks a joke or seems maddened by anything. Like his color palette, he is very grey. He doesn't talk about his past much, although does seem to have a soft spot for Rose Quartz.
Onyx doesn't trust very many people, emphasized by the fact that he will only fuse with a select number of Gems (such as Pyrite and Emerald). He isn't a strong believer of Gem-human mating but doesn't mention it to others. He, like Pearl, likes to visit space from time to time, spending long periods on the moon; hoping to speak with Lapis Lazuli.
I may not be the most skilled of Gems but that doesn't make me weak!
Onyx possesses traits and abilities that are common among all Gems.
Onyx pulls his hammer from his gem and is well trained with its use. He is flexible and can endure much physical pain without going down. After his days as a gem miner Onyx became accustomed to using slam attacks with his hammer. He is not very good at duel-wielding but is excellent with single handed. Aside from Emerald, Onyx is submissive when fused and only occasionally takes control.
- When fused with Pyrite they form Sunrock
- When fused with Emerald they form Serpentine
- When fused with Pyrite and Emerald they form Chrysolite
- Hammer proficiency: With thousands of years training and working as a miner Onyx has grown accustomed to wielding his hammer outside of combat but has proven to be very skilled. He uses bold movements with powerful strikes at unsuspecting points
- Shape shifting: While all gems have this power, Onyx has attained great uses in his forms, able to shift into more complicated forms than most gems.
- Shield projection: Unlike Steven's shield, Onyx can project a small shield capable of deflecting energy blasts or reflecting weak energy beams. His shield isn't very strong or durable but can come in handy at certain times.
- Shock wave: Like other Onyx's, Onyx can produce a shock wave from his hammer and fists.