The Day of the Departed is a sacred holiday celebrated by the people of Ninjago. Once every year, the citizens light lanterns to commemorate their fallen ancestors and friends, while also spending time with their families.
Following the Sky Pirate conflict, Ninjago celebrated the holiday once again, coincidentally falling on a Yin-Yang Eclipse, with the ninja spreading out across the land of Ninjago to remember their ancestors. Zane remembers Dr. Julien at Birchwood Forest, Kai and Nya remember Ray and Maya at their blacksmith shop, Lloyd and Misako remember Garmadon at the Corridor of Elders, and Wu remembers his father at the Monastery of Spinjitzu, while Jay spends time with his parents at their junkyard.
In the meantime, Cole goes to the Temple of Airjitzu to settle his debt with Master Yang. However, a sinister plot by Yang leads Cole to free the spirits of the ninja's old enemies from the Departed Realm, including Samukai, Kozu, Cryptor, Chen and Morro, all of whom possess statues at the Ninjago Museum of History. Seeking revenge, the revived villains spread throughout Ninjago to confront their adversaries.
- 84. Ocean Invaders! (mentioned)
- The holiday seems to be a combination of several different traditions from many different cultures, including Halloween, Memorial Day, Día de Los Muertos (The Day of the Dead), and Chinese and Japanese Lantern Festivals; it involves costumes, candy, celebrating and honoring the dead, and lighting lanterns for one's ancestors. In particular, it seems to draw inspiration from the Japanese festival of Obon, a similar holiday to Día de Los Muertos in which the spirits of one's ancestors are honored.
- People also settle their debts on this day.
- The Royal Blacksmiths have a song based on this holiday, entitled "Be my Day of the Departed Baby."
- October 29, the US air date for "Day of the Departed" in 2016, can be considered the real-life "Day of the Departed" date.
- The Day of the Departed is "a unique Ninjago holiday. A bit of everything" and is "inspired by holidays all over the world."
- The same lanterns used on the Day of the Departed were used during Dragon Day. It is unknown whether this is because the holidays are somehow connected or just the same lanterns being used.