I don't know if this belongs here, per se...but I figured I'd ask since I just came across it the other day and have been following this thread with some interest. Is there any interest in a Dungeons & Dragons Electronic Labyrinth game? I actually have no idea what's inside of it, though since it's presumably fairly primitive. I can probably pop it open and look at chips if someone wants.
I have a good bet it's probably a TMS1xxx in there, going by the age. Checking out on ebay, it looks like it runs on a single 9V so that reenforces the TMS1xxx theory.