Dragotron

Dragotron is the main antagonist of the Japanese Transformers anime, ''Transformers Go!. ''He was also known as the "Demon Emperor" due to his vicious and terrifying personality. He was also a leader of the Predacons, a team of evil dragon robots.

In the past, Dragotron and his Predacons brethren were originally created by the Decepticon scientist called Shockwave in a hope of molding them into an army for the Decepticons. However, Dragotron and his army rebelled against the Decepticon masters and scattered across the universe. Taking notice of the planet called Earth, Dragotron and his band of Predacons decided to attack Earth, only to be defeated by the alliance of both Autobots and Decepticons, resulting them to be sealed away in the depth of Earth with the use of the mysterious Legendisc.

History
Dragotron was once sealed away by a blue Legedisc in Mount Fuji in Japan