|“My father and my uncle, Ninjago's two greatest Elemental Masters.”|
|— Lloyd, The Hands of Time|
The Sons of the First Spinjitzu Master are the children of the creator of Ninjago. The brothers, Wu and Garmadon, were a team who defended Ninjago for a millennium, prior to the era of the Ninja and long before the First Serpentine War. Together, they fought many great evils of Ninjago's past, such as Aspheera, the Skulkin, the Serpentine, and the Time Twins.
After several millennia of protecting Ninjago, the First Spinjitzu Master eventually felt his time was nearing its end. Wanting to continue his legacy, he fathered two children: his firstborn, Garmadon, with power over Destruction, and Wu, his second-born, with power over Creation.
When the two were young, Garmadon went to retrieve Wu's katana after knocking it over the monastery wall during a sparring match. While reaching for it, he was bitten by the infant Great Devourer, which would go on to be a known as legendary being that could grow forever as long as it consumed, and whose venom could turn the purest of things wicked. The young Garmadon was corrupted by the venom, causing him to become increasingly villainous over time, but it would take many, many years for him to be completely taken over. When they became young men, they swore to protect the Golden Weapons after their father's passing.
The Serpentine were wreaking havoc on Ninjago, raiding places like Jamanakai Village and terrorizing those living there. The Elemental Masters formed an alliance to battle the Serpentine and protect the citizens. At Jamanakai Village, the Elemental Masters drove back the Serpentine Tribes, but were forced to retreat upon the arrival of the Anacondrai. A crucial battle in the war took place at Birchwood Forest, with the Elemental Alliance fighting Arcturus and his Anacondrai, but this battle was lost as well. The Elemental Masters found hope by using the Sacred Flutes to hypnotize the Serpentine and imprison them in a series of tombs. Arcturus and the other Anacondrai generals were found guilty of committing war crimes, and were consequently banished to the Cursed Realm.
Shortly after the Serpentine War and the banishment of Chen and Clouse, the Elemental Alliance were celebrating their recent victory against the Serpentine, two of these celebrants being the Hands of Time. Acronix and Krux, the elemental masters of time, betrayed the Elemental Alliance, believing that they had the strongest Elemental Power in Ninjago. Wu and Garmadon gathered the Elemental Alliance to fight the Hands of Time, but they were outmatched.
Wu, seeing his team losing, gathered Ray and Maya and asked them to forge four blades made of Chronosteel. Ray and Maya used all their energy to create the Time Blades, to the point where they had passed out. One evening Wu comes and gathers the Time Blades from Ray and Maya. He returns to the monastery, leaving the gate open so that the Time Twins would come.
A raging battle between the Time Twins and the Sons of the First Spinjitzu Master broke out. The Twins, unaware of the Chronosteel Time Blades, tried using their powers against Wu and Garmadon, who were holding the blades. This powered the Time Blades with the four elements of time (Forward Time, Slow Motion Time, Pause Time and Reversal Time). Wu and Garmadon then created a Temporal Vortex using the four blades and allowed the Time Blades to be sucked into the vortex. The Time Twins did not surrender, instead following the Time Blades and entering the vortex. At this time Wu saw a blimp that showed Acronix's return forty years in the Future.
- Wu and Garmadon are part Oni and part Dragon, like their father.
- However, unlike their father, they are also half-human.
- Originally, Wu and Garmadon rarely used their Elemental Powers. However, from the eight season onwards, Garmadon uses them as his primary method of combat after learning of his True Potential.
- Despite Garmadon being the older of the two, Wu appears to look older when they are both old men. However, this is mostly due to him having lighter hair and a beard. When the beard on his minifigure is removed, it can be seen that he and Garmadon share nearly identical facial features (i.e. age lines).
- The brothers have made multiple enemies who have sworn a vendetta towards them: Aspheera, Samukai, and the Time Twins.