Rainbow Dragon the Great Spirit

The Rainbow Dragon the Great Spirit is a Duel Monster Spirit, who is the Creator of the Rainbow Power Stone and the leader of the Dragon Stone Guardians and was one of the servant of Rock Ōtsutsuki. Ayame Muto is the Descendant of the Ōtsutsuki race associated with Rainbow Dragon.

Pre-Mega Man ZX Shippuden
10,000 years ago, the Rainbow Dragon is the leader of the Crystal Beasts as it battled Bauzire, leader of the Koopa Clan.