In the original version of Toon Wars, Ponies Unleashed, Twilight was corrupted by a cosmic entity and transformed into a bestial assassin for it. It used her to kill the rest of the Mane 6 but failed to remove Rainbow Dash and Twilight's real self from the equation. Since I couldn't think of a proper way to anthrofy her, I borrowed designs from Equestria Girls to help out. In the story, she actually got a few upgrades too and looked more and more like a dragon hybrid until she finally grew paws and dragon wings.

Side note: For an early aspect of Toon Wars, Ponies Unleashed is surprisingly the darkest one yet, having almost every character die in an extremely brutal fashion. It's honestly expected of a fanfiction made by a 12-13 year old, really.