4bit mono ADPCM, 8.080 kHz sample rate.
Not a request, but I wanted to rip this one...always liked this game.
The hardware is quite powerful (a 68000 with a full TMS34010 as the VDP) and could be worth exploring for future homebrew projects.

Here is a nowoffline interview with one of the developers (thanks to the good people at the Internet Archive for preserving it!)
http://web.archive.org/web/2022010616...