Easyy choice.

I only way I know of Cloud is because of KH, and he's really emo and mopey in the KH series. I LOVE Sora! He's one of the my favorite fictional characters.

^Crisis Core gives nice insight to Cloud's character, but then it goes backwards to the direction of KH Cloud once FFVII and Advent Children happens.

^I just hope we see cocky and slightly arrogant Cloud (I've heard he's like that in other games) in Kingdom Hearts III. What exactly happened to him to make him so emo and mopey? I think I'd like to see some livelihood in him. He's an excellent fighter, though. I loved fighting alongside him for a short period of time in KH2.

Cloud is a bit cocky, but more-so he's just a bit rude and indifferent to situations.
I haven't watched Advent Children in a few years, but I remember him being mopey there.

As for wondering why he becomes mopey? Crisis Core. The answer is Crisis Core hahah. Like I said, he was kind of a nice, not exactly cheery, but a good-spirited guy in the beginning, but the events of Crisis Core change and shape his character completely. God forbid he used to smile and laugh in CC.

I will give him that though, he's an excellent fighter (after CC, in CC he was pretty near useless). If we were to tie in his mopey attitude and why he's like that for KH3, then it's probable we'll get some appearance of an older Zack.

This gives a little more insight to his nature in Crisis Core /watch?v=H-8uXbMSH88

^I actually remember watching a scene where Zack died (correct me if I'm wrong), which made me sad, because I thought he was awesome in Birth By Sleep.
The links actually don't work. I think you need to do [ url= *insert web address here* ] * Insert title * [ /url]
Except with no spaces.

Just copy that onto the end of the youtube.com site and it'll work. I've had bad experience of trying to get links to work in Fanpop poll comments for some reason.

Lol, well, yeah, you encountered the big spoiler then xP That scene is even harder to take once you play the whole game and everything that builds to that moment...
But he could appear in KH3 solely on the premise of Aerith being in KH2. Because the entire gaming world knows that she died, yet she's there while Cloud is in his getup that he only wears after Aerith's death.

OMG that was so easy!