Original brief description:
"The LION is a distortion device and a clean booster with two complete circuits that can be mixed independently.
Has a bypass footswitch and boost footswitch that gives extra distortion.
Great for bass -- distortion that doesn't cut out the low end.
Great for guitar -- minor chords retain clean harmonics -- you can get great distortion but still hear definition of notes."
You can find original DIY thread and schematic here.