You know when Roxas enters the old mansion near the end of the prologue? He draws something on the table in the library to make the ground open up and reveal the hidden basement. One symbol was that of the Heartless and the other was the Nobodies. The one Roxas drew was purposefully hidden; you can't see it if you watch the video. I think it may have something to do with the Chasers, in the secret ending of KH2. Many have said they think the Chasers are the three seen in the video, but I don't think so. They may be another being created when a Heartless is. The heart= a Heartless. The other Ansem Reports say the body= a Nobody. Could the soul= a Chaser? Roxas seems to draw it without realizing it, sort of. Maybe he subconsciously knows what the Chasers are, or knew while in the Organization, before being defeated by Riku. That means the other Organization members may know about them too. And DIZ must've known, because he's the one who put it there. They may be the subject of King Mickey's message after the credits in KH2, and the focus of KH3. This doesn't really explain the secret ending, though. What does anyone else think?