The Skeleton King

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The Skeleton King is the main antagonist of the Hyperforce throughout the show. His servants include the Formless.

Origin
The Skeleton King was originally the kind and humble alchemist who lived in the region that will be named in The zone of Wasted Years. He was also a friend of Captain Shugazoom, who requested him to make a substitute heroic force, which will later be known as the Hyperforce. At one stage, the Alchemist were studying Netherworld, which contained a group of evil beings termed by the Verron Mystics as the "Dark Ones". Captain Shuggazoom was at first worried that these evil creatures would breach the barrier the Alchemist created, but he assured him that they are all safe. Unfortunately when Captain Shuggazoom left, Mandarin was fiddling with the control, releasing two of the creatures into the world: one; a demon-like being who subdued the Alchemist, and another; a worm like being that would eventually become the Dark One Worm.

He was another main antagonist along with Shadow. He used Formless monsters to against them inculding Samuel. He is destroyed along with Chiro until death by the explosion. He was returned in Operation Overdrive, but he was been destroyed again by new DriveMax Super Ultrazord. He is revived in Energo Zoids, but his third fate for good by Dillian Joo and his Liger.

Trivia

 * Skeleton King's voice actor, Mark Hamill, is known for playing Luke Skywalker in Star Wars and playing The Joker in several Batman animated series.
 * Though it does not show, Skeleton King still cares for the Monkey Team (his former self, the Alchemist's feelings for them never left after his soul was taken).
 * His voice tone was used in Batman the Brave and the Bold as the Spectre in "Chill of the Night"!
 * He has a room of Chiro's toys, indicating if he's obesse of destroying Chiro or he could be Chiro's father.