Isn't the way to defeat them obvious? At least with the created ones, all we have to do is find out who's creating them, and how, and put a stop to it. We'd take them down at the source, then destroy whatever Heartless were left.

[It seems that straightforward, but even as Zuko says it, he's not sure. Things are never that easy.]

Another way of getting information is from people who know how to control the Heartless. There's some guy called Hades who knows how to do it, right? And Joluk said that in the Land of Dragons, there are people there who can do it too. We need to get information from whoever we can -- and put a stop to them, if they're allies with the darkness.