ripvanwormer wrote:Gamma Terra, from the Gamma World RPG, connected to the D&D universe through an artifact called the Alternate World Gate (described in The Book of Marvelous Magic).
The worlds of the Boot Hill, Top Secret, Dawn Patrol, Star Frontiers, and Gangbusters RPGs, all accessible through the Alternate World Gate.
Note that Dawn Patrol
was a board game, not an RPG. But it was published by TSR, so it got an Alternate World Gate.
: Earth during World War I.
: Earth in the 1870s Western United States, or thereabouts.
: A spy-themed RPG. The 1987 version featured a secret intelligence agency called ORION facing off against an evil group called WEB.
: A science fiction setting taking place near the galactic core, so not really "Earth," but there are humans, so maybe there's an Earth somewhere in this universe.
: This is Earth in the 1920s and 1930s, centered in a fictional Lakefront City on the western shore of Lake Michigan.
: This is a post-apocalyptic Earth (Gamma Terra) with mutants and robots. The nature of the apocalypse varies, but nuclear war is normally involved.
Of course it's possible that these are all the same planet at different times.
There's also Midgard, a version of Earth based on Norse mythology, treated in The Northern Reaches Gazetteer
as an outer plane.
And the Star*Drive
setting for Alternity (and d20 Future). The alien Fraal from that setting ended up in one of the AD&D Monstrous Compendiums.
I suppose you could also count the Earth of Elric of Melniboné (this setting is often called the Young Kingdoms after the human nations that followed the decline of Melniboné, but author Michael Moorcock always called it Earth; after the novel Stormbringer
, it transforms into our world, or something like it). It appeared in Gods, Demigods, and Heroes
and the first printing of 1st edition Deities & Demigods