Clay Moorington the Nexo Knight has had enough of Monstrox, Jestro and their Forbidden Powers and decides to take the fight to them. But the Cloud of Monstrox is getting closer and closer to unleash his master plan.

The Cloud of Monstrox is inside of The Stone Colossus and it now stands in front of Knighton. The students of the Knights Academy are mobilized, the King and Queen are on the defence and the Nexo Knights are ready for the final showdown.

The giant Stone Colossus is marching on Knighton. Ruina the witch tries to get to Clay, but the other Nexo Knights need him in their final defense of the realm. Which side will he choose? Family or friends?

Using his Stone to Life magic the Cloud of Monstrox turns Clay into a living, fighting, breathing stone fighting knight. But will Clay use his forces to fight for good or for evil? Does he have a choice?

Clay wakes up in the poor town of Nothing Hill which literally has nothing. Will Clay remember who he is and what he is fighting for? His friends try to help him, but Jorah Tightwad and his Bots get in the way.

Things are getting dire in Knighton. Jestro and the Cloud of Monstrox only need the Forbidden Power of Awesome Annihilation in order to reveal what's hidden in Mount Thunderstrox. It can't be nice.

Jestro and the Cloud of Monstrox builds a new stone army from giant building blocks to crush Knighton. The Nexo Knights try to convince Rockowski, a demolition expert, to help them.

The Nexo Knights decide to use Clay to infiltrate the enemy camp but first Clay needs to learn how to be a good spy. Agent Shield, Jack Shield helps them with that.

Jorah Tightwad is digging for gold but finds the ancient Lord Krakenskull buried with his army. This stone army is exactly what the Cloud of Monstrox needs.

After a magical explosion, Jestro discovers that he still has the Book of Monsters and together they decide to attack and destroy the Kingdom. Their monsters seem like too much for the new Knights of Knighton until an old friend emerges in a new form.

When Jestro and the Book of Monsters start using their monsters to ravage the countryside, the Knights get an awesome new HQ to fight him, the mighty, powerful Rolling Castle known as the Fortrex.

During the graduation ceremony for the new Knights of Knighton, Jestro the jester is ridiculed for his terrible, uh, jestring. Distraught, he's seduced by the powerful and evil Book of Monsters until Merlok the Magician tries to stop Jestro by using his most powerful magic spell.

Clay and Lance tussle over who should lead the Knights and protect the King who's toddles off on a PR tour of the kingdom. While fighting off Jestro and his monsters, Lance realizes that nobody knows the Knights' Code like Cla.

Party time in Knighton! The mood is down so the King decides to throw a party. In the meantime Jestro attacks the Fortrex, but he is confronted with the new Nexo Power "The Wedgie of Doom".

Seeing Jestro's monster army about to destroy the King's Castle, Aaron rides off to gather his cohorts. In the meantime, the King and Queen bravely go out to defend the city against the monster menace. Is this the end of Knighton?

The Knights explore a strange forest looking for a Book when Jesto unleashes the Book of Fear on them and a new monster, Whiparella, uses her minions to induce the Knights' worst knightmares.

Jestro and the Knights are both trying to get the Book of Deception. But the book has used its powers to create a powerful maze in the Hill Country, near Axl's home, and it's a race to complete the maze and get the Boo.

When the Knights of Knighton can't defend the outer villages of the kingdom, a mysterious Black Knight appears to take on Jestro and his monsters. Who is he really and is he a new ally or a new foe?

When Lance stars in a movie about the Knights, the Book of Monsters want to eat the script to learn more about modern society. Jestro uses his spy, Lavaria, to infiltrate the set and attack the Knights.

Jestro uses the baddest book yet, the Book of Destruction, to make monsters that capture the Knights one-by-one so that he can turn his attention to attacking the King's Castle.

When the Nexo Knights are sloppy in a fight with Jestro, Merlok 2.0 sends them back to the Knights' Academy. Not only for a brush-up but to find out what Jestro is after in its hallowed halls.

When Jestro uses the Book of Greed to rob Auremville of its riches, he also gets Lance's parents as prisoners and these demanding rich folks are too much for even monsters to handle.

The Knights are tasked with protecting the King's valuable Ned Knights comic book during the Bookingheim Knight-a-Con. But with all the costumed kids there, will they recognize the real Jestro and Book of Monsters coming to get them?

Rival to the King, Jorah Tightwad thinks his knights, the Tighty Knighties, are easily better than the Nexo Knights, so he challenges King Halbert to prove who's better during the King's Birthday Tournament.

Axl and Chef Éclair must enter a cooking contest to try to keep Jestro from getting the hottest chili recipe in the realm.