A stallion who stood by Princess Celestia's side on the night of Nightmare Moon's banishment, the infamous Night of Nightmares. Despite what the history books would tell you, it was much more catastrophic than simply being the night the royal sisters fought. No, it was much, much worse. On that night, those who used dark magic to control demons suddenly found their summons rebelling against them, and soon the entire night transformed into a demonic massacre that saw towns built on witchcraft destroyed and thousands — both innocent and those who practiced the dark arts — died in unimaginable agony at the hands of the Tartarean monsters. This stallion, Canto, and his wife Angela, were the only nobles of their town, Contrapasso, who braved the demonic hordes to secure Celestia's safety, and they ultimately comforted her as she mourned the banishment of her sister.

Some time later, Angela, who continued to practice dark magic because her expertise made her well-trusted, was fatally wounded by her own demon, and died. Her unfortunate end sent Canto into a spiral of sorrow and anger, eventually leading him to the conclusion that he must… now, get this… travel to the future to eradicate any and all dark magic users, using a towering, gargantuan phoenix statue which he christens the Caelum.
…So yea, he's basically Balder from Bayonetta 2 if he decided to make The Savior from Devil May Cry 4…