So I was playing that mini-game on Nick, because I'm freaking obsessed and wanted spoilers, and I got them. Turns out Zuko's alive yet! Old as fuck, duh, but alive. :) Perhaps Basco will be doing Zuko's voice, if we get to see him.
So in retrospect I was curious about seeing lighting bending being used in factory work and by gang leaders. I thought it was specialized due to difficulty, but was it just less known and required some mainstream teaching like metal bending?
The way Iroh explained it, it was VERY difficult to master. But youngsters have a way of picking up supremely difficult things very easily, so I imagine that as the world population and technology grew, so did education.
And maybe the Factory hires Firebenders and then teaches them to bend lightning.
So I was boredly clicking around when I came across this spoiler (set): Spoiler Link It contains images: What appear to be flashbacks images with what looks to be Sokka, Aang, Toph... Also I think it may be from Episode 4, as Ive read around it has been leaked (in part or full, I don't know)... I think... In any case, I stopped looking when I realised the nature and didn't want the spoilers myself (thus the reddit link)
So... I'm only semi-spoilt? but I figure others may like to see/know...