Who is still alive from the original series?
The easiest way to tackle this question is to list characters and their current known status:
- Aang Dead, confirmed
- Katara Alive, confirmed
Sokka Dead, confirmed : in Welcome to Republic City, Katara says :
Aang's time has passed. My brother, and many of my friends are gone.
Zuko Alive, confirmed : from The Legend of Korra: Welcome to Republic on nick.com , when you go in "Central City Station" and get the information about the Zuko statue, you learn that :
Three years ago, Zuko turned over the reins of the fire nation to his daughter. Officialy, he's retired, but unofficially, he still travels the world as an ambassador for world balance
- Toph Beifong Alive, Confirmed : She Is residing at the swamp.
- Appa Unknown
- Momo Unknown
- Iroh residing in the spirit world
- Azula Unknown
- Suki Unknown
- Mai Unknown
- Ty Lee Unknown
- Ozai probably dead : considering his age.
I don't know about Toph, she was the youngest of the Gaang - if she's dead, it probably wasn't of natural causes. Just because there's statues of you doesn't mean you're dead :)
@Tacroy Thats why I put *Unknown* as her status. Meanwhile, her wiki say she is death, but I don't think the reference they put conclusive because it just say "that whole generation has died". The key point is that Katara did survive and say "**many** of my friends are gone", which leave place to some other survival.
Zuko's alive. On Nick.com, it states that Zuko still travels though world, though he is retired. He has handed the Fire Nation over to his daughter.