Name: Cobrastrike; Cobrapaw; Cobrakit

I love this name

Age: A long time after he got his full name (sorry if this isn't specific enough, but Idrk what to write)

I'd prefer if you would put even a rough estimate

Gender: Male

Personality: Because of the way he was raised, Cobrastrike comes off as cold to every cat he meets, but if you become his friend, he's super nice. He's really mean towards cats who are mean towards his friends, but if you insult him, most of the time, he'll just shake it off. It's mainly insulting his friends/family that makes him angry.

Cold, yet nice, mean, but unruffled, very nice balance of traits

Appearance: He is a cat with gray, dark gray, cream, brown, and white fur, all kind of mixed together. He has some black markings on his face along with a pair of yellow-green eyes.

Beautiful and detailed

Clan: FireClan

Fanclans are always nice

Rank: Warrior

Mother: Viperfang (gray-and-white she-cat with blue eyes)

Thank you for including the description. And I love that both Cobrastrike and his mother have snake-related names

Father: Falconclaw (gray tom with cream splotches; green-yellow eyes)

Amazing description 

Sibling: Silverkit (gray she-kit with cream splotches and blue eyes; she's dead)

Poor Silverkit

Mate: None

Kits: None

Backstory: Cobrastrike was born in FireClan to Viperfang, only to find that his littermate, Silverkit, and father, Falconclaw, was dead. He was also a descendant of Fireclaw, the founder of FireClan, who had done some terrible things, and looked scarily similar to how Fireclaw was described. His Clanmates always looked at him with disgust in their eyes (even they rejected Fireclaw, even though he was the founder), and said mean things about him. All those, he could shake off. The only thing that he couldn't let go was when they said mean things about Viperfang, which was quite frequently. Finally, one day, Viperfang got into an accident, and none of her Clanmates bothered to save her because she, too, was Fireclaw's descendant, and Cobrastrike wasn't there. Furious, the tom battled the cat who could've saved Viperfang but chose not to. The leader, who had been looking for him to show any signs of violence, exiled him instantly. He became evil and wanted revenge. His plan worked, but he died soon after and went to DF. 

What was his plan? Did they insult him simply because of how he looked? Did they ever give him the chance to prove himself? What accident did Viperfang get into? How did Falconclaw die?

Extra: idk

You did very, very good with your OC. 7/10