Especially in Japan i think KH3 will sell amazingly well, when i saw it was coming out I got quite excited which is rare these days for me.
The only problem with the kingdom hearts series is that with all the prequels and shifting characters the story is quite confusing for people new to it so newcomers to the series could end up having their minds screwed XD
Everybody who liked the older ones though will no doubt pick it up though so i'm sure it'll sell pretty well.







