Board Thread:Fun and Games/@comment-25512318-20180206200410/@comment-26537965-20180421143554

Trevor7626 wrote: The Overlord is the creator of the Stone Army and the source of all Darkness in Ninjago. A sinister dark entity, he first appeared as a manifestation of Darkness itself that challenged the First Spinjitzu Master. After a lengthy battle, the First Spinjitzu Master succeeded, defeating the Stone Army and trapping the Overlord on the Dark Island. Thousands of years later, Lord Garmadon was confronted by the Overlord's spirit, who influenced him to join forces. Garmadon assumed command of the Stone Army, which constructed an ultimate weapon. Eventually, the Overlord revealed he was using Garmadon and possessed his body—commencing a metamorphosis that turned him into a giant dragon. The Ninja and Lloyd returned to Ninjago, where Lloyd fought and defeated the Overlord in the final battle.

Some time later, the Overlord once again returned in the form of a spirit. With the help of Pythor and the Nindroids, the Overlord became the all-powerful Golden Master using the Golden Weapons and Lloyd's Golden Power. In a final effort to defeat the Overlord, Zane sacrificed himself, destroying their physical forms. As the balance must be maintained, the Overlord survived, yet his spirit is dormant. A statue of him will be placed in the Ninjago Museum of History.

He's not dead. Never has, never will. Even, if he is not dead, his spirit will likely be dormant for thousands of years. And btw copying a wiki page is not a valid source.