I've been thinking about Guru Pathik
I saw several other discussions about him that are months old so I thought I'd share my personal breakdown.
Who is he? He is said to be a "spiritual brother" to Aang's people aka the air nomads, so he is not a nomad, or if he is he's not an airbending.
In both shows we see various characters using far sight to see across the planet. Aang, Toph, and Guru Pathik. Toph and Aang are both earth benders.
Now the air temples are said to be unreachable by those who can't fly, but they're built on the peaks of mountains. The only other bender that could reach that would be an earth bender (or a comet-boosted fire bender). So personally I'm convinced that he is an earthbender.
He is also an ancient man, a friend of Gyatso, so at least 112 years old. Now the only people we know who were able to extend their lives were earthbenders.(Kyoshi, and the assassin)
When I started writing this I had a final thing I wanted to mention but I forgot. :( Thoughts?