Overlord

The Overlord, also known as the Crystal King, is the manifestation of all evil in Ninjago and the overall main antagonist of the LEGO Ninjago series. He is final boss of Legacy of the Green Ninja, and the main antagonist Rebooted and Crystalized.

Long before Time had a name, the Overlord manifested in the dark corners of Ninjago. He fought against the First Spinjitzu Master during the War of Creation and was banished to the Dark Island for thousands of years. After being imprisoned there for thousands of years, Lord Garmadon would discover the Dark Island and ignite the prophecy. Overlord possessed Garmadon and was finally able to crossover back into Ninjago. There he was defeated by Lloyd, the Ultimate Spinjitzu Master.

However, his spirit possessed the ground where he was defeated, and infected the Digiverse, which was created right over it. It would take the help of the Ninja and Zane's sacrifice for him to be defeated seemingly once and for all.

After a buildup of hatred and malice over the years, the Overlord would yet again return with his final plan by recruited past villains and an army of indestructible Vengestone warriors. He would only be defeated once the Ninja sacrifice their Elemental Powers for good and erase him from existence.