Ummmmmm... a keyblade?

 

 

Who could it belong to?

 

...

 

Hey, there is someone in the water!

 

Let me help you...

 

Um, you do know the opening cinematics and that teaser cinematic were completely symbolic, right? Nomura said so himself, they aren't literally going to happen, at least not that way. Sora reaching his hand out to Aqua in the water is just symbolic of the fact that he's going to save her in KH3 and him picking up the Master's Defender is symbolic of his (hopefully) becoming of a Keyblade Master within the game. Not everything depicted in cinematic openings, trailers, and secret endings literally happen within the events of the games, but they may sometimes be recreated in other different ways, like I'm sure Sora will have a moment where he's reaching out for Aqua's hand somewhere and maybe Sora will have a scene where he picks up SOME Keyblade, just not necessarily the Master Defender.

Ummmmmm... a keyblade?

 

 

Who could it belong to?

 

...

 

Hey, there is someone in the water!

 

Let me help you...

 

That trailer isn't canon.

 

 

So then....Sora never saves Aqua from the realm of darkness. He'll save Aqua from drowning at the Destiny Island beach.

 

Instead Aqua escapes the realm of Darkness and ends up in Destiny Islands....her Keyblade washes up on the shore and Sora picks it up......and then he notices a body in the water. He rushes over and pulls her out of water.

 

Hence Sora saves Aqua (not from the Realm of Darkness but from a sea of water)