Boreal

Boreal is Zane's loyal dragon that can be awakened using the Ice Staff. He is also the fearsome and dreaded ice dragon that guards the Castle of Ice. Zane used it to freeze the village of the Formlings and the Great Lake.

Early life
At some point, Zane was stranded in the Never-Realm and encountered Boreal who he was able to tame. Boreal became his loyal dragon, and will awaken with the Ice Staff.

The Last of the Formlings (Flashback)
After the Formlings refused to align with Vex, he persuaded Zane to attack the village. Zane, who had became the Ice Emperor, ordered Boreal freeze the village, leaving most the citizens frozen. The lone survivor, Akita, had watched in horror and attempted to attack Zane and Vex but Boreal impeded her. The ice dragon attempted to attack her though she was saved by her brother Kataru who clawed the dragon's wings. However, Kataru was apparently frozen in the process. After seeing the villains leave, she then swore revenge on them.

Wasted True Potential
Zane saw him in his dream, freezing Great Lake and all five other Ninja.

The Belly of the Beast
Zane saw Boreal in his dream again.

Secret of The Wolf
Zane chooses to release Boreal to attack Great Lake. Once the dragon wakens from Zane's staff, the beast emerges and flies out to Great Lake.

My Enemy, My Friend
Boreal flew by the mountains and headed for the Great Lake, with the Ninja and Krag catching sight of it. Boreal headed to the village, where it proceeded to freeze a majority the villagers. Kai tried to hold off the beast, though he was unable to stand a chance. Boreal ended up freezing the entire village, leaving the Ninja horrified. Boreal later made its way to the Castle of Ice. Along the way, it encountered Lloyd, and they battled. Akita tried to help but was knocked aside by Boreal. The Ice dragon ended up destroying the Titan Mech, defeating him. Boreal moved to finish Lloyd, though Vex contacted it and told it to spare the weakened Ninja who was brought before the Emperor and learned the identify of the Ice Emperor as Zane.

Appearances

 * 70678 Castle of the Forsaken Emperor

Season 11: Secrets of the Forbidden Spinjitzu

 * 99. "Wasted True Potential" (dream)
 * 102. "The Belly of the Beast" (dream)
 * 121. "Secret of The Wolf"
 * 122. "The Last of the Formlings" (flashback)
 * 123. "My Enemy, My Friend"

Trivia

 * Boreal means the "north or the northern regions."
 * It also relates to the climatic zone south of the Arctic.
 * Boreal is Zane’s third dragon.
 * Boreal was the one that recovered Kataru as a prize for Zane.