IGN (I know they suck, but at least they're good with some things (news their reviews are bias as hell, but another thing for another day)) article proof.

So yeah, we're gonna be Pro-Bending in a bonus mode in the upcoming LoK game from Platinum Games.

Personally I can't wait, this is one thing I've missed since Air, I mean Pro-Bending was awesome, can't we all agree on that?

3600042 Maybe they'll come back to it in Book 4. Otherwise, it's probably a case of "Early Installement Weirdness". Book 1 was set mostly in Republic City, whereas Books 2 and 3 involved the Water Tribes, the new Air Nomads, the Earth Kingdom, the Metal Benders, and the Spirit World. Though Book 3 did start out in Republic City.

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Still, it was awesome.

I'd buy a whole game about it, you know like how they made that Quidditch game.

Make a team, and raise through the ranks.

3600194 I'd like that, especially if they avoid the biggest problem with the Quidditch World Cup where it became rather repetetive after the first couple of games. The inclusion of super moves, and special bending powers for different teams would be really cool. For example, Bon Lin's super move could have him lava bend.

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I'm not sure that would be legal.

Remember there are rules, though maybe if they had some kind of system like some boxing games have where you have a reputation.

You could cheat, but that wouldn't be good for you since the public would start to hate you.

According to the pro bending rules, "specialized moves" are forbidden. That includes lightning bending, metal bending, probably bloodbending (not that anyone used it), and now, almost certainly lavabending.