There was also a really cool image way back in the old loose leaf 2e Monster Manuals. It was on one of dividers that came with the set. It showed a group trying to get past a beholder type guardian critter (spectator maybe) by feeding it a big hunk of steak. Very cool image. Can't find it though on Google and I have no idea who did it.
or, as others have said, just about any Elmore from this period fills me with nostalgia.
For some reason more than any other of Tim Truman's works, this immediately takes me back to sitting on my bedroom floor, reading through 1e books.
As has already been said lots of times, pretty much anything by Jeff Dee but I've always remembered this pic.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.