Nadakhan is the captain of the Sky Pirates, the owner of Misfortune's Keep, and the last living Djinn. Many years ago, he put together his crew and dominated the seas of Ninjago, until he was faced with a rival, Captain Soto. Soto trapped him in the Teapot of Tyrahn while his crew was marooned across the Sixteen Realms.
Centuries later, upon the destruction of Djinjago, Nadakhan became the last of the Djinn. Shortly after the Battle of Stiix, Nadakhan was freed by Clouse; he set off to claim the Realm Crystal and reunite his crew.
After learning of his lover's demise, and seeing the destruction of Djinjago as a result of the Ninjas' actions, Nadakhan's father gave him a mystical sword to capture the souls of his adversaries and tear Ninjago apart to rebuild Djinjago. In addition to this, he planned to marry Nya so he can grant himself unlimited wishes. Nadakhan's crew refurbished Misfortune's Keep and began rebuilding Djinjago in a series of landmasses above Ninjago City. In the ensuing conflict, Nadakhan captured Nya and trapped the Ninjas' souls in the sword.
Nadakhan completed New Djinjago, and after he and Nya were married, he betrayed his crew. During a final fight with the Ninja, Flintlocke incapacitated Nadakhan with Tiger Widow venom, though the venom accidentally struck and killed Nya. As a result, Jay made his final wish, which was that recent events had not transpired and Nadakhan was never freed from the teapot.
Though he's still alive, Nadakhan is trapped in the Teapot of Tyrahn, which is lost in the wreckage left from the Battle of Stiix.