The Bison, obviously.

But we are talking about Iroh and Aang!

Iroh is a giant carnivorous bison, who eats the puny penguin otter Aang.

There is no battle. Iroh wins.

The hell man? This argument makes no sense! Iroh is an old man who can firebend,

Aang is the most powerful being of his time!

Theres no competition!

But Iroh is a beast who can kill who he pleases because he is so overpowered.

Ok: If Chuck Norris went against God in a fight, who would win?

No, Aang has all the elements and the Avatar State. To quote Fred Weasley,

”Size is no guarantee of power.”

THIS IS A FIGHT BETWEEN IROH AND AANG!!

Exactly, and Aang kicks ass.

Buff Iroh kicks everyone’s ass! No further comment.