Plato was a timesharing system I used in elementary school in
the late seventies. It had monochrome graphics. Several dungeon
adventure games were available, at least one of which was multiplayer
and had first-person single point perspective graphics. I also
remember regular bird's-eye view version(s).
(Plato also had a multiplayer space war game, empire/0empire,
which lives on today as "conquest".)
And while I'm asking, does anyone know the solution to Deathmaze 5000
by Med Systems Software? (Invert and telephone!)
I just did a google search for "plato moria" and got some
hits. There's one that mentions a Plato reunion in 1997,
so there may still be some remnants of the community out there.
Go to http://MarcDashevsky.com to send me e-mail.