|“That's sufficient to start the growth process for a few warriors, but creating a large army requires a very specific environment. A swamp. They are using a swamp.”|
|— Skales, "Secrets Discovered"|
The Vermillion Swamps are swamps located somewhere near Ninjago City. They serve as the main headquarters for Krux and Acronix's Vermillion forces. It also houses the Vermillion Dome of Doom. They are connected to the Ninjago Museum of History through the sewers of Ninjago City.
Krux and Acronix were inside the Vermillion Dome of Doom and were trying to get Cyrus Borg to work. However, Borg complained about the lack of building materials and refused to work. Machia then came in and forced Borg to work. At the same time, the Time Twins felt the effects of the Slow-Mo Time Blade and usher Blunck and Raggmunk to retrieve the blade.
In the end, Blunk and Raggmunk informed Machia that they were unable to retrieve the blade, but Machia insisted they will get it back.
The Time Twins scolded Bluck and Raggmunk for losing the Time Blade, then lying about using and losing the Time Blade. Blunk and Raggmunk tried to come up with a plan for taking it back, but it would allow the ninja to locate their hidden base.
The Vermillion take back a captured Wu as well as the Slow-Mo Time Blade back to their headquarters.
Later, Cyrus tried stalling but Machia threatened him.
Cole and Jay found the workers, but they were caught by the Vermillion and forced to fight their way out. Meanwhile, Lloyd briefly had Wu, but he is taken back by Bluck and Raggmunk. Meanwhile, Zane has a tough time locating Cyrus Borg due to the fact that Machia took him on a Vermillion ship. Finally, Kai and Nya made their own discovery; finding Ray and Maya in the Dragon's Forge. However, they were caught by the Time Twins who take Kai and Nya as hostages and threatened them to retrieve the Reversal Time Blade.
The rest of the ninja spot Kai and Nya and were about to help; however, more Vermillion start attacking them.
Cole, Jay, Lloyd, and Zane continue to fight the Vermillion and after the Vermillion think they have destroyed the ninja, they head for the Vermillion Dome of Doom. However, the ninja are still alive and disguised themselves. During their heist, they discover Borg and he tells the ninja about a deactivation code on the Iron Doom.
Before they could do anything, they were spotted by the Vermillion and start fighting them. Out of nowhere, Samurai X comes flying in and helps Borg get to the top while the rest of the ninja tried to hold back the Vermillion warriors. However, Borg is too late as Krux and Acronix returned from their journey and freeze Borg. The Time Twins then activate the Iron Doom and travel back in time.
Cole, Jay, Lloyd, Zane, Samurai X, and Cyrus Borg were stuck at the Vermillion Swamp hoping Kai, Nya, and Wu could save Ninjago. They then spot Maya and a weakened Ray and Lloyd quickly identified them as Kai and Nya's parents. Ray explained that Kai and Nya went back in time because the Time Twins have the Reversal Time Blade which is the only device which can stop Ray's rapid aging.
Back in time, when a young Wu yielded to Krux and Acronix, the present-day changed as Borg is seen without his BorgWatch and Zane is inactive due to not being built.
However, this doesn't last for long as the past is quickly restored allowing Borg's technology to stay and Zane still being alive. Soon later, Kai and Nya crash into the Vermillion Swamps with the Reversal Time Blade while Wu stayed on the Iron Doom. The ninja used the Time Blade to restore Ray's health and the ninja promised to find Wu.
- 69. "A Line in the Sand"
- 70. "The Attack"
- 71. "Secrets Discovered"
- 72. "Pause and Effect"
- 73. "Out of the Fire and Into the Boiling Sea"
- 74. "Lost in Time"
- 5. "Golden Hour" (flashback)