While wandering through level #9 of a dunjon, in search of another Orcus, I stumbled upon a Demogorgon, and knew right away, that this was it. It’s a demon, and it has an Orb. The orb is now mine.
2 Orbs recovered, and 8 left to go.
The dunjon to the right of the castle is where I found the second Orb. Now I’m off to find more dunjons.