This is Sable a Zebra who's also an alicorn. The color of her magic is the same color as her cutie mark.
She can be seen wearing a skull upon her head, her blue eyes are visible through the sockets and her horn sticks out from where the crown of the skull is missing. When wearing it she has her hair as a mohawk.
The "necklace" she wears is (much like the skull) just a fashion statement, the cat eye stone can be changed out at any time. She either wears her curly layered hair as a waterfall braid or in a mohawk style.
Art by myself