3rd enemy (by Namine's drawing)

[JET73L]

The third symbol on the Heartless/Nobody/Blank triquetra in the abandoned mansion in KH2 looks like a crown in Namine's drawing and a stylized crescent scythe (like a sideways 'crescent moon with nose') on the table when Roxas draws it (likely due to distortion of the angle, or his poor drawing skills, it looks too curved to be a crown there).
The crown could mean 3E are the denizens of the true Kingdom Hearts. The heartless factory from KH1 and the city from KH2 are either the Heartless- and Nobody-constructed versions of Kingdom Hearts, or they are the atria to the true Kingdom Hearts. If the are merely entrances, and not alternate versions, Sora will have to fight his way through something similar to get to the true Kingdom Hearts at the end of KH3. It's also possible that 3E is humans or the Keyblade Knights (being the guardians/denizens of Kingdom Hearts), and the first two versions of KH are the split Heartless and Nobody versions of the actual Kingdom Hearts. Sora must fuse the two previously-seen kingdom Hearts' together. If the "keyblade desert" scene is in the future, or in the Crossroads of Time, he's long dead of old age and they must bring him from the past to either restore the balance of light and dark or restore their homeworld, respectively depending if 3E is human or Keyblade Knights.

[bond of flames 2.0]

I take it you havn't seen the secret ending from the KH2 Final Mix + game...Check it out it might change some of your theories...And every body says something about that drawing...I didn't see anything. And my question is how did Roxas know to draw the other sign it could've been anything as the right drawing to open up the floor. Other than the fact it was the programming of the game for him to draw the right thing but taking it from within the game perspective how did he know?

[JET73L]

1. KH2FM+ is out in the US, or are you talking about Japanese version/Youtube?
2. If you look at Namine's Drawing, on the "You Recieved _____" page, it has the completed drawing, with the third symbol. Roxas just completes the drawing on the table, so it matches Namine's drawing, and doesn't know what it's supposed to do.