Kingdom Hearts » Secret Ending

In order to see the hidden ending, (actually it's more like a teaser than anything else) you need to have the following when you finish the game:

Reminder: You MUST collect all your prizes from the Dalmatian's House, since the secret ending will not appear if you didn't!

Wait until The End of the Credits to See it!

I'm not going to reveal anything about it here. You just have to see it for yourself.