Nya
Her costume is usually something scary, like a vampire or a witch. Spends time with Kai and her parents, now that they're back. It's her favorite holiday, so she goes all out with the lanterns and festivities. Loves going to late night parties, sometimes coming back at 5:00 am
Jay
He goes all out with his costume, sometimes making it himself. Eats a ton of candy and gets really sick afterward. Hangs out (among other things) with Nya. Stays the night as his parents looking through old photo albums
Cole
Tells the Sensei Yang story to whoever will listen. Doesn't usually dress up, but has a great time in Ninjago city, and loves all the street life. Always goes to see his father's performance and sometimes does an act himself
Kai
Spends the night catching up with his parents at the blacksmith shop. Will sometimes go to parties, but only if his friends are going too. Like Jay, eats a lot of candy. Uses his fire power to light lanterns for little kids. Wears something really flashy for his costume
Lloyd
For him, DOTD is about remembrance, so he and his mom visit the corridor of elders and light a candle for his old father. Even though Garmadon is back,
neither of them think of him as the real Garmadon. They choose to remember him when he was good
Zane
Doesn't completely understand human holidays, but celebrates just the same. He'll light a candle in front of his father's statue and spend the rest of the night with his friends. Sometimes dresses up, but not often
Wu
Refuses to have any fun, no matter how hard the other ninja beg. Meditates, lights lanterns, and drinks tea.
Ronin
Gets completely drunk and tries to rob people's houses
