Was predicting that one. 😄
Keyblades have the power to seal/counter hearts of worlds (or Kingdom Hearts, the heart of all worlds). Keyblades are made to be overpowered that it's what the next sequel will be based mainly on.
Sora and Riku with ordinary weapons wouldn't stand a chance against a thousand heartless.
Keyblades that aren't of the like of those possessed by the three in this video, or "fake" keyblades. The one(s) possessed by the Keyblade wielder (the villain and his doppleganger) have the real Keyblade which can be used to reveal the heart of a world (near the end of this video). Real keyblades also have keychains attached to them giving them unique appearances.
YouTube video
lmao...
Anyway, Birth By Sleep is a PSP game that takes place after two and before three (assuming there'll be a KH3, of course. The title MAY turn out different).
There are prequels such as KH:352/6 days (don't know what the hell that's supposed to mean) for the DS, and another KH prequel (with Mickey being the focus) for mobile. Way to go Square Enix, not.