Lord Garmadon is the Master of Destruction, as well as the ninja's archenemy-turned-ally and former mentor. He is the First Spinjitzu Master's firstborn son, Wu's older brother, Misako's husband, and Lloyd's father. Garmadon grew up learning the art of the ninja alongside his brother. As a child, Garmadon was bitten by the Great Devourer and infected with evil, which led him down a darker path through which he would be continually tempted during his time as one of Ninjago's heroes.
Around the time of the Serpentine War, Chen had Garmadon sign Wu's love letter for Misako, leading her to choose Garmadon. Misako had a son named Lloyd, whom he cared for deeply despite his corrupted soul. Ultimately, he lost himself to the venom's influence and became an evil warlord, banished to the Underworld after a climactic battle with Wu.
After allying with the Skulkin and Serpentine to claim the Golden Weapons, Garmadon later joined The Overlordโonly to be used as a vessel for his rebirth. After Lloyd defeated The Overlord, Garmadon was purified of evil and reunited with his family, hoping to atone for his misdeeds.
Garmadon became Master Garmadon, and during the Nindroid crisis, he grew closer to his son. After Zane sacrificed himself, Garmadon and the ninja journeyed to an island to rescue Zane. There, they were caught up in a conflict with Master Chen and his cult. Garmadon was banished to the Cursed Realm in a bid to defeat Chen's army. Later, during the ghost's invasion, Lloyd met with his father one last time and wore his robes into battle. When the Preeminent was drowned by Nya, Garmadon died in the Cursed Realm's destruction and passed on to the Departed Realm.
Lloyd honored his father's life by pursuing the role of a master. In time, however, a criminal syndicate known as the Sons of Garmadon sought to resurrect Garmadon's evil form. Harumi led the group to success, reviving Garmadon as a monster with no good left in him. After nearly killing Lloyd and seemingly defeating the ninja, Garmadon reigned as Emperor Garmadon and wreaked havoc across Ninjago City.
He oppressed its citizens and sought out his son, who led a brave Resistance. After Wu and the original ninja returned to Ninjago, Lloyd defeated Garmadon by refusing to fight, and his father lost his powers. Garmadon was sent to Kryptarium Prison but warned of coming darkness.
When the Oni invaded, Garmadon managed to convince Lloyd to release him, to help the ninja fight. After using the Tornado of Creation with Wu and the ninja to vanquish the Oni, he headed off to parts unknown. He encountered the people of Two Moon Village, fought against Kuma's bears and the Red Crows, led by Lord Mogra, and came to a new understanding of the conflict within himself.
Garmadon later moved into an apartment with Vinny, the cameraman of NGTV, continuing to learn about empathy by nurturing a plant named Christofern. However, once the Overlord and his Crystal army attack Ninjago City, Garmadon breaks his vow of peace and helps to teach Lloyd about unlocking his Oni Form. Subsequently, he assists the Ninja to fight the Overlord. Following the defeat of the Overlord, Garmadon replants Christofern on a distant mountain and joins the ninja and their many allies in rebuilding the Monastery of Spinjitzu.