Might as well throw mine in…
My alien oc, Leokah (she's not part of any existing fandom, just a oc I made at random).
short version of her backstory is that she comes from a planet that is know for having very fierce warriors, and the part she is living in is currently under a civil war between two very large tribes, and she is stuck in the middle of it (one side wants to get the rest of the tibes on the planet to be ruled by them, the other wants to wipe out all the other tribes to make them the only tribe left).
She would later end up captured by slavers after most of her village was attacked, and was forced to serve under the brutal rule of a slaver gang, until she was eventually freed by a bounty hunter hired to kill the slavers.
Since her race have a very high sense of loalty, they have a sort of "blood oath" to tohers (basically, if someone saves them form dying, they becoe loyal to them, out of respect for it. Rejecting this is very much frowned upon, and has even resulted in death to a few that refused to follow this). She is now the partner of the bounty hunter (both professionally and romantically).
Her skills is that she is very agile and strong, and knows how to use a wide variety of wepaons, such as blades, blunt objects, guns (both laser wepaons, and more convensional lead based wepaons), explosives, and is also trained in unarmedcombat and martial arts.