Metal Heads are from the game series Jak and Daxter. If you want to know more about them, read here: http://jakanddaxter.wikia.com/wiki/Metal_Heads

I don't know what I'm going to name her yet, but what I have so far on her story in mind is that she was one of Metal Kor's offspring that was a far more rare type of Metal Head than the others. She was favored by him greatly in her skill to wipe out large crowds of enemies and strategically battling using the environment around her.

After the death of Metal Kor, she along with a large population of the stronger metal heads survived, she being the mother and breeder to revived the near-extinct species, soon forced herself to genetically adapt to the harsh wastelands. She developed wings, which were strong enough to slice through three inches of solid steel in one swipe, and also used more for combat than flight.

She would place pieces of her fallen ally's armor onto herself, genetically fusing it to her person. As she adapted and evolved into a stronger self, she grew three skull gems instead of the usual single skull gem. This is most likely due to her forced evolution, causing much noticeable changes in a short period of time.