Return of the Overlord

Return of the Overlord is the twelfth episode in the second season of Ninjago: Masters of Spinjitzu.

Plot
When the Celestial Clock's countdown finally completes, a mighty beam of energy strikes the Stone Army's camp. As the energy fades, the Overlord proudly introduces Lord Garmadon to their completed ultimate weapon: the Garmatron, a massive, heavily-armed tank. As Lord Garmadon gazes in awe, a pair of Stone Soldiers arrive with Nya as their prisoner. The latter declares that her friends will find a way to stop Lord Garmadon, but the villain simply stuffs an apple in Nya's mouth and uses her as the "first test subject" for the Dark Matter.

Meanwhile, the heroes return to the beach, where Dr. Julien asks about the horns he just heard. Sensei Wu explains the situation: the Celestial Clock has ended its countdown, the final battle is about to begin, Lord Garmadon's ultimate weapon is operational, and Nya is a prisoner of the Stone Army. Kai assures a worried Jay that Nya will be too tough for the villains to break, and they will see her again. Sensei Wu turns to Lloyd, who is still dejected over the prospect of fighting his father, and reminds him that it is his destiny as the Chosen One - all of Ninjago depends on his victory. Misako tells her son that Lord Garmadon is just as reluctant at the prospect of battling his son, and the other Ninja pledge their assistance in the final fight.

Reinvigorated by his friends' support, Lloyd leads the charge on Lord Garmadon's base camp, only to find it deserted. The Falcon leads them to massive tracks and a path of destruction leading towards the coast - Sensei Wu realizes that the ultimate weapon is not meant to attack the Ninja, but to achieve Lord Garmadon's dream of remaking Ninjago in his own image. Misako is horrified - the resulting influx of evil will upset the balance of the world, allowing the Overlord to return in full - and Lloyd resolves that they can't let Lord Garmadon fire a single shot.

The group moves on, but Zane is forced to say goodbye to his father, who is unable to keep up and decides to head back to the Destiny's Bounty. As they run, the Ninja reflect on all of their adventures, but the jovial mood is broken when they sense an evil presence nearby. Suddenly, a crimson Spinjitzu tornado hits Cole and Lloyd, and stops in front of the group to reveal Nya, corrupted by the Dark Matter into a feral slave of Lord Garmadon. Sensei Wu realizes that the villains are trying to buy time to fire the ultimate weapon, and he, Misako, and Lloyd carry onward while the Ninja attempt to subdue Nya without hurting her.

The Garmatron finally reaches the coast of the Island of Darkness, where the Overlord tells Lord Garmadon to show Ninjago his power. At General Kozu's command, Stone Soldiers begin loading Dark Matter bullets into the cannon, but Lloyd, Misako, and Sensei Wu arrive before Lord Garmadon can fire. To the Overlord's dismay, Lord Garmadon leaves the controls to confront his family - despite their pleas, he insists that the only way they can be together again is if he corrupts the entire world with the same evil that has consumed his being.

With that, Lord Garmadon activates the Garmatron's cannon, only to discover that it has a twenty-second warm-up period. Misako deflects blasts from the tank's side cannons, allowing Lloyd to jump aboard; however, General Kozu manages to pin the Green Ninja down long enough for the Garmatron to fire. The warhead soars over the ocean and bursts into clouds of darkness over Ignacia, draining the color from the land and transforming the people into snarling, purple-eyed beasts. Lloyd attempts to summon his powers as the Stone Army loads another round, but Lord Garmadon activates a trap door that drops Lloyd and General Kozu out of the Garmatron before firing again.

Back in the jungle, the Ninja are having a rough time against Nya, until Zane realizes that they can use their elemental powers on the environment instead of their opponent. He uses his Elemental Blade to break the chain of Nya's weapon; Jay creates an electric barrier to deflect thrown needles; Cole blinds Nya with a cloud of dust; Kai cuts down a nearby tree so its leaves surround his corrupted sister. Finally, Zane freezes the tree, leaving Nya trapped within a dome of ice - wryly commenting that "this club just became boys only," Kai leads the others down the Garmatron's trail.

The Overlord begins cackling as the Garmatron's second shot corrupts Jamanakai Village; below, Lloyd laments his failure, but Sensei Wu assures him that he did his best. Misako realizes that the balance has been undone, and the Overlord confirms that he is finally free to take over Ninjago. Lord Garmadon is infuriated at this, raging that Ninjago is his to conquer, but the Overlord reveals that it was never going to be his, shortly before a beam of white light engulfs the top of the Garmatron.

As the Ninja rush up to their allies, Lord Garmadon's hands morph into claws, his limbs lengthen, and the demented laughter of the Overlord issues from his newly-reptilian mouth. Sensei Wu tells Lloyd that the creature atop the Garmatron is no longer his father - the Overlord has possessed Lord Garmadon's body. Misako warns her son that the Overlord will show no mercy, but the Ninja offer their support once again - with determination, Lloyd leads them in attacking the Stone Army.

Seeking more evil power to increase his strength, the Overlord aims the Garmatron's cannon at Ninjago City, but nothing happens. Looking over the side of his vehicle, the Overlord realizes that the whole of his army is occupied fighting the Ninja, with Sensei Wu and Misako preventing the Stone Soldiers from bringing the next warhead to the Garmatron. Although General Kozu attacks Sensei Wu, the old master kicks him into the Garmatron's loading port - thinking that the next bullet is loaded, the Overlord fires, sending his own general flying into Ninjago City. General Kozu ends up crashing through the window of the Mojo Dojo, where Dareth sends his students to swarm the four-armed Stone General. Enraged, the Overlord decides to load the cannon personally, only for Lloyd to leap atop the Garmatron and challenge him to battle.

While Kai hijacks one of the Garmatron's turrets to back Jay up against the remnants of the Stone Army, the Overlord knocks Lloyd off of the tank. Their battle continues on the beach, briefly clashing with energy beams before Lloyd dodges and blasts his foe into the jungle. The Overlord quickly recovers and flies above the trees, delivering a brutal tackle that sends Lloyd flying. The Overlord gloats that he can keep this up for eternity, but Lloyd is alone - in response, Lloyd removes his mask and asserts that his father will never hurt him.

Lord Garmadon briefly asserts himself from within the Overlord, begging Lloyd to stay strong - the Overlord's confusion and shock gives Lloyd an opportunity to take the offensive. As they clash with their energy beams once more, Lloyd calls out to his father, whose struggles cause the Overlord to falter. As Lloyd pushes his power to the limit, the Overlord roars that his father is gone before overcoming Lloyd's attack, trapping the Green Ninja in a sphere of dark energy and hurling him across the beach. Misako and Sensei Wu rush to Lloyd's side as the Overlord finally turns the Garmatron's cannon on his foes, but the tank's next shot is blocked by the Destiny's Bounty, piloted by Dr. Julien.

Fed up with the interference, the Overlord creates a portal for his army, declaring that they will go to Ninjago City personally to finish the job. From the back of the Garmatron, Nya mockingly bids farewell to her brother as he leaps at the portal, only to fall short. Kai screams in fury and despair as the portal closes, leaving the heroes trapped on the Island of Darkness. Misako manages to awaken Lloyd, who wonders if he has failed the prophecy; Sensei Wu tells him that he did not defeat the Overlord, but he did not lose his life, either. Picking up a piece of the Destiny's Bounty - marked with the symbol for "destiny" - Lloyd muses that he didn't lose the battle, only the fight; the true clash between good and evil is far from over.

Trivia

 * This is the first appearance of the Garmatron, and the last appearance of the Destiny's Bounty. It is also the final appearance of Lord Garmadon as a villain - he will spend the final episode either possessed by the Overlord or in his purified form.
 * The way the Ninja pledge their assistance to Lloyd prior to their attack on Lord Garmadon's base camp references a scene from the film adaptation of The Lord of the Rings: The Fellowship of the Ring, where Aragorn, Legolas, and Gimli offer their sword, bow, and axe (respectively) to aid Frodo in his quest.
 * The episode title is similar to that of the third book in The Lord of the Rings trilogy, Return of the King.
 * Kai comments that "this club just became boys only!" after the corrupted Nya is incapacitated, mirroring Nya's own rationale for adopting the identity of Samurai X in the previous season.
 * When the Overlord reveals that he was only using Lord Garmadon in order to take over Ninjago, Garmadon yells that the Overlord "stole that from my playbook!" This may refer to the events of "Weapons of Destiny," where Lord Garmadon used Samukai to create a means of reaching a place where he could gain the power he needed to wield all four Golden Weapons simultaneously. It might also refer to "The Royal Blacksmiths," where Lord Garmadon claimed that he had only gone along with Sensei Wu's alliance so he could escape his dimension and return to Ninjago.

Errors

 * At the beginning of the episode, the Celestial Clock is shown completing its countdown and firing a beam into Lord Garmadon's camp to complete the Garmatron. However, this sequence is completely different from the events at the end of the previous episode (especially noticeable due to the "Previously on Ninjago" segment that shows said events moments before this sequence).
 * When Lloyd wonders why Lord Garmadon isn't using the Garmatron on the Ninja, he is wearing his old ZX uniform.
 * The Overlord fires a Dark Matter missile from the Garmatron's main cannon at the end of the episode, despite the Ninja apparently preventing him from loading the cannon after its second shot (although the Stone Army could have reloaded the cannon during Lloyd's battle with the Overlord or he loaded it by himself like he said after they prevented it the last time).