It's an interesting world, from what I've heard. I can't think of any other worlds I've heard of where kids leave home and are basically encouraged to go traveling around interacting with the wildlife.

[As Sokka talks again, he muses over what Red had told him about the Poké balls and what he had been provided.]

A power source capable of doing what a Poké ball can do is pretty remarkable, even for my world's level of technology. Something that small that can convert solid matter into concentrated energy isn't something I can imagine readily accomplish without symbology or alchemy.