I'm going to have to go with Earth kingdom.
Water Tribes FTW!
I can't decide, but so far, I'm liking the fire nation.
Fire Nation FTW!
Water Tribes! =D
Water Tribe XD
Lets go AIR!
The Earth Kingdom!!!
Water Tribe and Earth Kingdom, since my favorite charcter is Toph.(yes, it IS spelled that way.)
Fire and Water...>,< Can't choose!