Calyrex’s name was erased from history when a spiteful king wanted to assert their divine right over the land. Only a northern village kept the truth safely hidden. That village’s crops were the most bountiful in the kingdom until the spiteful king razed their fields.
Pokéfeature: Calyrex can ride willing Pokemon to create a Rider form. Rider forms have their own movesets.

Glastrier was tamed through compassion and mercy. After riding Glastrier for three days and nights, Calyrex was beaten and bruised. Calyrex used its power to heal Glastrier instead of itself, and the horse never bucked again.

Spectrier’s pride never diminished, and it would go on to challenge Calyrex one hundred times over the king’s reign. When the people’s faith diminished and Calyrex’s strength grew weak, Spectrier was the last to leave.