Aang - Aang expresses his inner villain and dresses as Voldemort.

Katara - She’s either a kitty or a witch. And she adds her own Water Tribe touch.

Toph - Creepy lolita or some creepy version of a fairy tail character like Red Riding Hood.

Sokka - He either goes back to being Wang Fire or goes for the food related costumes like dressing as a taco.

Azula - I can see Azula dressing up as one of the fire signs. And she goes all out with face paint and everything. That or she takes the less serious route and dresses as a skimpy version of Zuko for the lols.

Mai - Doesn’t get a costume at first because she couldn’t be bothered but then Azula makes her dress as the Mother of Faces, because irony.

Ty Lee - Cheerleader. Sounds simple but she adds her own little Ty Lee circus quirks and it’s almost as elaborate as Azula’s.

Zuko - He is the comic book nerd who dresses up as one of his favorite superheros, adding a cybergoth touch. That or he tries to get vengeance on Azula by dressing as a skimpy version of her. Either way around they go at it in the costume contest.

Iroh - No one knows what Iroh dressed as but many are fairly certian that he’s either the one in the cute panda suit or the badass headless horseman.

June - We all know she has a Shirshu fursona.

Ozai - He’s a vampire because he’s not very creative.

Lo and Li - Fred And Gorge Weasley. Or they are the two with the scariest demon costumes.

Suki - The moon. Because nothing is scarier than the ex-girlfriend.

Yue - Skips the other phases of the moon to become full.

Ursa - Dresses as Noriko and pisses everyone off because the costume is both witty and typical at the same time.

Tom-Tom - His parents dressed him up as a cute little pumpkin but the minute they looked away he became the blue spirit.

Cabagge Man - Dresses up in a tux, Halloween is the one time that he can pretend to be a successful cabbage merchant.

I love this poll :D it's a great idea :)

Thanks. ^_^