I think it's tarlock (sp?). I think the whole fire bender killed my family thing is a lie. I think he is taking away bending but he's doing it by using chi blocking plus water bending to some how super block the chi flow of benders. He wants to be the only bender in the world because that would possibly make him the strongest person in the world. Some holes to be filled but it's what I came up with.
Edit to add to this.
So you know where I came up with this I was thinking that we all know that it's possible to heal a person from a chi blocking as well as control a person using blood bending so why isint it possible to make a chi blocking worse using bending? It seems possible since we are mostly water and if chi or pressure points can be affectedby water bending healers it should be possible to do in a combo.