Houou

Houou is a PokéGod. It is a real Pokémon named Ho-oh, but before Pokémon Gold and Silver came out, it was known as Houou.

Origin
Houou was one of the first PokéGods alongside Pikablu and Mew. It is especially similar to Pikablu and, to a lesser extent, Togepi as all three were based on real Pokémon. It was first known as Rainbow Bird, Golden Bird or even MissingNo. It was often known as the secret, fourth Legendary Bird alongside Articuno, Zapdos and Moltres. It was also known as the Fire- or Psychic- and Flying-type evolution of Moltres. It was thought to only be found in the Japanese Green Version of the game