My personal theory is that Amon wants to use her to de-legitimize the avatar as institution and by proxy all of bending. Perhaps he might do this by triggering her Avatar state in the middle of Republic city. Imagine the damage that could cause, thousands could be killed and the Avatar blamed. The Avatar has always…

The use metal cuffs to capture the generals (how else to capture master earth benders) but they are not metalbent, just regular somewhat awesome handcuffs

Additionally I see it as it was Toph's blindness that allowed her to make the discovery. Most people couldn't see the earth in metal, but Toph she has used Earth to "see" her whole life, and thus could feel the earth in the metal, invented metalbending where many generations of earthbenders had never even thought to…

The creators specifically rule out genetics in The Fortuneteller by having two identical twins one with and one without bending ability. Katara's parents are non benders so are Tophs. What  they have in common is culture, waterbending culture + spirituality leads to waterbending ability. We can assume the same with…

I say leave genetics out of this, that mitoclorian shit is bad enough. Let's call it a spiritual inheritance.
What we know about becoming a bender:
Your parents don't have to be a bender of that element: Katara
But it seems to help: everyone else
It's not strictly genetic:The fortuneteller episode in which identical…

I've always taken this episode to be confirmation that benders can't generally bend elements within people's bodies. That is Katara couldn't steam someone alive, or rip the water out of them, Aang couldn't bend the air out of peoples lungs. Bending is more of a spiritual power than one that strictly follows physical…

Bending seems to not be genetic. In the episode the fortune teller there are two identical twins one a bender the other not. I assume this is the creators saying that bending is magic/mystical and not genetic. Could be cultural, can't I assume be learned… or can it, the original benders learn it from animals.