A normal everyday horse, who has become something unbearable.
It started off as a fine horse in the stables of Khan Noonien, and later its ownership passed on to Khan Singh. One day, it was loaned to Mnemon Isoroku and Jess. Then it was stolen from them, killed, and forged into a hideous necromantic monster, a gift to Isoroku from his Abyssal Mate. It tried to kill itself, but Isoroku stopped it. Finally, Candeo and First Gust were moved by its plight, and cast it from a cliff. The horse believed it had been freed, but Withered Rose found its mangled body and kept its spirit from escaping. She rebuilt it, stronger than ever, and brought it back to Isoroku. He secured it near Whitewall, where it was eventually discovered and hacked to pieces by the terrified Guardians who found it. Once more, the horse believed that it could finally and truly die. It was wrong. Withered Rose rebuilt it once more, gathering what few pieces she could find, and constructed a necromantic version of a Swift Rider. It can no longer run, only watch events through its one remaining eye, and cry out to any who might hear it.
The Horse wants to die.
It doesn’t want to go back to the life it had. It knows that is impossible.
It doesn’t want to be given a pasture in the Underworld. It knows that would never be as good.
The horse has been given a tormented intelligence by Withered Rose’s ministrations, and it uses every ounce of that intelligence to try to plead, taunt, cajole, enrage, or otherwise instigate its own complete destruction.