Kingdom Hearts 1 - PS2 - Halloween Town Part III

Start at the bottom, making your way slowly up, smashing the glowing purple
orbs along the way, including the one on the platform behind his head. You
can make this battle as long as you want, and there seems to be a steady
supply of Gargoyles spawning should you want the extra experience. Taking
out the lanterns could also help, as those are Oogie's best weapon against
you.
Ansem's Report 7 and the Holy Circlet are yours, along with a Gravity
upgrade and the Pumpkinhead.
All the rest is epilogue. Don't forget to return to the Manor Ruins once
stood and pick up some goodies.
Once you're back on the Gummi Ship, you'll notice a new area between Halloween
Town and Atlantica. What could it be?