In Ecruteak City, there were once two towers that rose up towards the heavens. One day, lightning struck one of the towers, and three Pokemon who were trapped inside perished in the resulting fire. A rainbow-hued Pokemon descended from the sky and gave the three new life, along with new power. One became Entei, who holds power over flame. One became Raikou, who controls lightning. And the last became Suicune, who is one with water.

The three Pokemon and the Rainbow-hued one then vanished, and have not been seen since.