Zelda dark world theme, followed by the main theme.
Yes, it's long. Originally this was 2 tracks, but it felt wrong to separate them, since there is countermelody part which appears as a variation in both tracks - just something I added to keep things interesting.
The theremin comes in at 7:50
Hardware:
NES running the midiNES cart
Modified Midi gameboy (arduinoboy) running mGB
Moog Etherwave Plus Theremin
Software:
Renoise
Ableton Live for recording theremin