Edit: I added the second side of her!
I re-made my pony cause I didn't like her old design. I actually gave her a cutie mark this time! I am joining the bandwagon and adding a bio now too. I need a trotting pony icon now...
Name: Nabbie Lynx
Residence: She roams from all over, it's not known her exact residence.
Cutie mark: A mask of happiness and distress that represents her severe split personality disorder.
Bio: Nabbie suffers from a severe case of split personality disorder. She has only one alt which she can spontaneously snap into at any given moment; though sometimes it can be driven by an incident or somepony.
Her happy (or 'normal') side is the personality she is mostly associated with. She pretty normal for the most part, she enjoys partying, making friends, and sometimes even taking on the odd competition from the toughest colt in town. Although her appearance may seem like she's prissy she actually enjoys some good ol' rough housing and hoof wrestling.
When Nabbie is becomes overly angry or depressed she will switch over into her alter ego, Naberius. When she is in her Naberius alt her eyes change shape, color, and appear more serpent-like. Her mane and tail become ragged, her body language becomes unpredictable, and she usually goes on a psychopathic homicidal rage. Naberius often uses her own strength or magic to butcher her prey but sometimes she will use her favorite weapon "The Bleeding Ax" (a long handled ax that is constantly bleeding at the blade) if she wants a clean cut. Naberius also cannibalizes her prey.
Like split personality disorder in reality, Nabbie is unaware of her alter ego's existence. Nabbie doesn't know that she is really a cold-blooded killer and even when confronted with it she will have no idea what you're talking about. Most pony folk keep a distance from Nabbie because everyone knows that Naberius could strike at any moment. Nabbie doesn't have a real home, she is often exiled from any place she tries to reside in. She roams from town to town hoping one day she can find a place that she can call home.