The Book of Monsters catching a cold means trouble for the NEXO KNIGHTS when he can create an entirely new kind of “snotty” monster.

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

Never fear – Aaron is here! For this battle, Aaron is charging up and using The Sword of Merlok to help him beat these monsters! This Merlok Power creates a giant sword that falls and lands in the middle of the battlefield, causing huge cracks in the ground that deal area-of-effect damage to all enemies. Additionally, golden eggs fall from the sky, crushing enemies beneath them.

Robin wants to join the NEXO KNIGHTS heroes in battle, but he is too small. Robin starts developing extra legs to make him taller and ends up developing the powerful Ultra Armor. The knights use the ultra armor to defeat the monsters even more easily than before. All cheer Robin's great idea.

When the other NEXO KNIGHTS decide they need a vacation from Clay, they send him on a holiday not knowing that he’s going to a resort that houses an evil book or that Jestro will be heading there, too.

Clay has arrived to the battlefield ready to fight, but he needs some help! Watch him power up by summoning The Crossbow of Merlok with his shield. With this special Merlok Power, a mounted crossbow appears in the middle of the screen and shoots in a circular motion for 20 seconds, dealing area-of-effect damage. Every 3 seconds, the crossbow stops and then starts to rotate again in the opposite direction.

Clay takes a walk in the forest. Monsters follow him. He thinks back to when he was young and started dreaming of becoming a knight and did his first heroic act. The monsters attack him, but he thwarts their attack and defeats them easily. Macy and Aaron are mad he got in a fight without them.

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?