|Kai||Kai (Shadow of Ronin)||Kai (The LEGO Ninjago Movie)|
| "That's not what happened at all!"
This article is about something not canon to the storyline of the TV show, Ninjago: Masters of Spinjitzu, or the LEGO Cinematic Universe.
|Weapon of choice||Obsidian Sword|
|First Appearance||LEGO Ninjago: Shadow of Ronin|
|Voiced by||Charlie Schlatter (LEGO Ninjago: Shadow of Ronin)|
After relocating to Spinjago, Kai retold the events on Chen's Island to the other Ninja, though his description was greatly exaggerated with everyone complimenting him and wild twist. Following his story, the Ninja began to train but that was interrupted by the arrival of Ronin who stole the Ninjas' memories using the Obsidian Glaive.
In the hopes of finding a way to restore their memories, Wu sent the Ninja to speak to Hibiki at Kryptarium Prison. After dispatching with Ronin's goons, they learned of the Inky Lemonberry in the Toxic Bogs and went to pick up Nya from Ed & Edna's Scrap N Junk. To get there, Kai used his Blade Cycle, through quickly fell under attack by Blade-Cycles and Rattlecopters.
Once arriving in the Toxic Bogs, Kai expressed concern about eating something that grew in such a hospitable place. Nevertheless he drank the Tea of Insight and learned that in Obsidian Sword was hidden in the Fire Temple.
Kai accompanied the other Ninja to the Frozen Wasteland where Zane acquired his Obsidian Sais. There, Zane remembered that Ronin was who took them to Chen's Island and he and Cole recapped Zane's death for Jay.
Before they could go to the Lightning Ruins to retrieve Obsidian Nunchucks however, Nya called Kai reporting that the Nindroids were attacking New Ninjago City. Kai and the other Ninja caught up to Nya in the park just as a jet crashed into the nearby Fireworks factory. Upon talking to Cyrus Borg, Jay was overjoyed to learn that his Lightning powers would be vital to stopping the Nindroids, and the Ninja quickly headed to the Floating Ruins. With the power of lightning once again at the Blue Ninja's command, the Ninja were able to shut down the power and deactivate the Nindroids. Their victory was short-lived however as Ronin soon arrived and attacked the Ninja using the Lightning Forge, forcing the Ninja to retreat.
Later, Master Wu realizes that Ronin plans to bring back Chen. To avoid this he sends Jay, Cole, and Dareth to recover the Forge of Ice. Meanwhile, he, Kai and Zane recover the Forge of Fire which is inside the mouth of an active volcano. After recovering the forge they reunite with Jay, Cole, and Dareth. Suddenly Ronin ambushed them with the Lightning Forge, though Dareth and Zane managed to escape. After recovering the last two forges he release the Ninja.
Back in Spinjago, Sensei Wu realizes that Ronin needs the Primal Fulcrum. They travel to the Fangpyre Cemetery to find Lloyd and Misako to help them. Unbeknownst to the Ninja, Ronin used the Obsidian Glaive to alter Misako's memory to believe that the Ninja had betrayed her. After finding the primal fulcrum, Misako tricks the Ninja into activating a fail-safe. After destroying the Obsidian Glaive, Ronin and his goons escapes destroy the entrance to the room to avoid being followed.
Later, the Ninja follow Ronin to Chen's Island to avoid him to open the portal to the Cursed Realm. But the Ninja did not stop and instead entered the now giant sized portal on their Elemental Dragons and the Ultra Dragon to stop him once and for all.
After they had searched different portals to find him and manage to build an entrance to the portal he was hiding in, they where finely standing face to face with Ronin for one last time, but Ronin then revealed a triumph card. Using the remaining power of the Elemental Forges, Ronin transformed himself into a giant elemental creature and fought the Ninja. But as the battle continued, the Ninja manage to destroy each of the Forges that powered his elemental form, until they where all destroyed,and Ronin was then forced to flee on R.E.X. once more, but not before he saw a giant, green, ghostly arm coming out of the now closing portal. After Ronin escaped, the ninja managed to escape from the Cursed Realm too. Then Kai points that Jay lost his pants again. However, this part turns out to be Kai exaggerating again, much to Jay's frustration.