They had other abilities, sure, and only a few, crackpot scholars doubted that a pegasus' ability to walk on clouds, or an earth pony's ability to accomplish tremendous feats of endurance, were anything less than magical. But when it came to spellcasting, the hornless races were shut out. Even those vile, verminous pony knock-offs, the Changelings, had a spellcasting leader with a horn!