The Tooth of Wojira is the fourth and final episode of The Island and the 164th episode overall of Ninjago. It aired on March 14, 2021, paired up with "The Gift of Jay."
As Jay is sacrificed to the sea serpent that terrorizes the island, the other ninja begin to suspect events on the island are not all as they seem.
Extended: Breaking free of their bonds, the ninja attempt to rescue Jay but are too late as he's taken by the sea serpent. When Lloyd makes an interesting discovery, they realize that the Keepers may have been manipulated. Jay finds himself in a cavern full of hoarded treasure where the real villain is revealed. Heroically, the ninja, and Twitchy Tim, come to Jay's rescue.
The Ninja attempt to free Jay from the boat to which he's been tied by the Keepers as an offering to Wojira, but are unable to do so before he is taken into the mist. However, Lloyd discovers evidence that the creature is a fake, and upon being confronted by Chief Mammatus questions how he and his ancestors came to guard the Storm Amulet. Mammatus explain that the First Spinjitzu Master himself charged their ancestors with safeguarding the artifact, for fear that Wojira would rise again and cover the world in water were she to regain it. However, Wojira-or what seemed to be Wojira-appeared recently, and someone posing as an islander suggested that the Keepers should offer up their treasures to the beast.
As the Keepers' resources became depleted, they eventually settled upon the sacrifice of a person, and decided upon Jay. Furious at this reasoning, the Ninja insist that the Keepers help them locate the false Wojira. They soon follow Jay to a hidden cavern filled with escaped prisoners from Kryptarium Prison, who prove to be under the command of Ronin. Having exploited the criminals to bleed the islanders dry, the corrupt bounty hunter attempts to escape, only for Twitchy Tim to arrive on a Keeper catamaran and crash into the fake Wojira. Ronin and his cohorts are then delivered to the Keepers, and Mammatus apologizes to the Ninja for all the trouble he has caused them.
The Ninja then discover that the Storm Amulet is missing from its resting place, and quickly realize that Clutch Powers is responsible. They swiftly capture the archaeologist with the amulet in his possession. Later, Wu and Misako find Lloyd staring out to sea, and he questions whether the real Wojira might indeed be sleeping somewhere beneath the waves. His fears are valid, as the scene shifts to an undersea chamber where a serpent lies asleep with another amulet embedded in its forehead...
Ronin's line of "And I would have gotten away with it if it weren't for you Ninja and your pesky friend!" is an obvious parody of the line often spoken by defeated villains at the end of Scooby Doo stories.