Found some samples from KH1 used as SFX. They are Sephiroths SFX and they all come from Zero G Ambient 1.
Zero 2 - Used when he is has successfully locks on to you when he uses the death spell. When you get that aurora around you as it comes in you hear like a hhhaAAaa voice effect which is in fact saying "Zero". (Kind cool and creative)
Monoilth - Uses a couple of times. When he is using meteor and supernova and the asteroids start spinning you start hearing this.
Belltress2 - This one is tough to hear. You hear it as he powers up and says "I am the chosen one" with that green aurora.
There is probably more in there.
Its hard to hear because the PS2s synth warps it into what the sound designers programmed it to do. I was able to hear the samples by extract them so i can hear what they sound like unmodded with no noise.
EDIT: Also Ocarina of time cave ambience.
http://www.youtube.com/watch?v=m9bjzC-x-uM at 0:06
Its SPACEOSPHERE from Ambient 1. You have to pitch bend them both the opposite way at the same time. Heres a little demo i made of it. Its not dead on put its what he used.
https://www.mediafire.com/?1hmfj8dbhojdlg2