The story starts in The First realm, also called the Realm of the Oni and Dragon, where the Oni and Dragons are at war. The Dragon had the power to create. The Oni had the power to destroy. Then comes the First Spinjitsu Master who is a child from both sides. Tensions grow between the 2 sides because both want the FSM to be with them. The FSM possesses naturally occurring elements. The FSM attempted to end the war using the Dragon Armor but failed causing him to flee the realm. There were 15 other realms.

Soon afterward, however, the Oni pursued the FSM into this realm, creating a temple deep within Primeval's Eye, where they depicted their origins on the walls of the temple. They would also seal away the Oni Mask of Hatred within the temple, which could only be taken by a being with Oni blood.

The FSM came upon a realm where a giant serpent, named Wojira, was attacking. Wojira had powers the FSM didn't have. But someone else was fighting Wojira, Nyad. She was the first elemental Master of Water. When all hope seemed lost, Nyad became water as a last resort to stop Wojira and did. After Wojira died, the 2 amulets powering it were given to 2 tribes. 1 for the Keepers, and the other for the Merlopians.

2 species emerged: the Humans and the Serpentine. The FSM had to rebuild this new Realm he came upon. He went to the Golden Peaks with some materials and forged the Golden Weapons, each charged by 1 of the 4 powers he possessed. The Nunchucks of Lightning, The Sword of Fire, The Shurikens of Ice, and The Scythe of Quakes (Earth). With those weapons, he recreated the realm in his image, naming it Ninjago.

He also created the Realm Crystal, a powerful device that allows the user to travel to other Realms, which looks like a blue diamond.

The FSM came upon a new evil: The Overlord, which had the opposite powers of the FSM.

The Overlord, not being able to withstand the powers of the FSM, created the Temple of Fortitude, which has a seal to protect against the FSM's golden power. At the temple of Fortitude, the Overlord was able to create stone warriors, which had armor that could withstand the power of the FSM. Meanwhile, on the opposite side of Ninjago, The FSM created the Temple of Light, in which the FSM drew a ton of prophecies. He created his mech, which he thought was able to fight the stone warriors, which didn't work.

At the battle, the FSM was overwhelmed by the thousands of stone warriors. So, he split Ninjago in half. The half where the Overlord and the temple of light were, was called the Dark Island, and the other had no special name. It was just Ninjago.

The FSM created the Monastery of Spinjitsu, in which the Golden Weapons were stored, and the FSM lived. Eventually, the FSM had 2 sons. Wu and Garmadon. The Overlord wanted to use one of the sons of the FSM as his vessel for his return.

The Overlord possessed a serpent, which at the time was small, which is to bite Garmadon and inject evil. Wu and Garmadon were training, and Wu's katana fell over the monastery walls. Garmadon decided to get it, and when he climbed up to the other side, the serpent (otherwise known as The Great Devourer) bit Garmadon. It would take years for the evil to fully corrupt Garmadon.

Wu and Garmadon were both Spinjitzu Masters. Spinjitzu is a martial art created by the FSM.

Wu and Garmadon went exploring and accidentally trespassed into serpentine territory, and were captured. The young serpentine princess Aspheera made a deal with Wu that if Wu taught Aspheera Spinjitzu, She would let them both out. Garmadon resisted but Wu agreed. Aspheera has yellow eyes with red-orange irises and looks like an Indian cobra.

Wu and Aspheera became best friends, or so Wu thought. Aspheera wanted to learn Spinjitsu so she could take over her kingdom and become the Queen. Wu and Garmadon had to stop her.

They discovered a darker and twisted version of Spinjitsu, which gives the user overpowering elemental strength. Wu and Garmadon fought Aspheera and locked her in a tomb. Aspheera swore revenge against Wu ever since.

There were other elemental masters, which were the Guardians of the FSM. After the FSM died, Garmadon went to train under Master Chen. Chen had another pupil: Clouse, who was the Master of Dark Majic. Clouse also wasn't an elemental master, just a sorcerer. Clouse and Garmadon were having a 1v1 in which whoever wins becomes Chen's right hand. Garmadon cheated and won from Clouses POV, but from Chen's POV, Garmadon did what he had to do to win.

The serpentine and humans were at peace which Chen broke by deceiving both sides. Garmadon and Wu liked the same woman: Misako. Wu sent a love letter to Misako, but Chen somehow got the letter and made Garmadon sign it. When Garmadon figured out that Chen wanted to break the peace treaty between the humans and the serpentine, Garmadon left him to reunite with Wu. Chen is responsible for the Serpentine War.

Chen broke the Elemental alliance, turning them against each other. If it weren't for the Sacred Flutes, which hypnotize Serpentine, The Serpentine would've won. The most responsible tribe was the Anacondrai, fierce, fast, and strong warriors. The 4 other tribes were locked up in tombs. The Anacondrai generals were cursed to the Cursed Realm. The remaining Anacondrai were in their tomb.

The elemental masters of Time, aka the Hands of Time, Krux, and Acronix thought they were superior to the other elemental masters. "Control Time, Control EVERYTHING," they said. Ray, the Elemental Master of Fire, and Maya, the Elemental Master of Water, were professional blacksmiths. They forged 4 blades out of chrono steel, a metal that takes away elemental powers. Wu and Garmadon had an epic 2v2 against the Hands of Time. The Time Twins lost their powers. Wu and Garmadon created a time vortex, which opened a vortex to time itself, and sent the blades in time. The Time twins went after them. Krux came out shortly after, but Acronix was lost in time for the next 40 years.

Misako married Garmadon and had a child. Then the evil finally corrupted Garmadon, turning him evil. He tried to steal the Golden weapons to recreate the world in his image. Wu stopped him and had a 1v1 fight with the weapons. Garmadon was about to win, but the spell on Wu's Kimono cursed Garmadon to the Underworld.

There, Garmadon engaged in a 1v1 against the King of the Underworld, Samukai. Garmadon defeated him and became the King of the Underworld. Misako sent Lloyd to boarding school.

Wu found a little boy named Morro, an elemental Master of Wind. Wu believes that Morro could be the prophesized Green Ninja, and this gets inside Morro's head. After the Golden Weapons doesn't respond to Morro, Morro leaves the Monastery, looking for the tomb of the FSM to show that he was worthy, and seeking to break destiny itself. Morro died in the Caves of Despair looking for the Tomb of the FSM, and his spirit was sent to the Cursed Realm.