Cosmos: The Secret Melody is, per the author, a science-fiction role-playing game that homages the earlier Ultima games, as well as several cult classic games from the 1980s (including Elite, Star Flight, and especially Sundog. The game aims to simulate a complete universe, comprising hundreds of millions of galaxies, billions of stars, and hundreds of billions of planets, all of which can be visited and explored (obviously, there is a heavy reliance on procedural generation). Planets all feature land masses, buildings, caverns and dungeons, and even underwater areas.

Additionally, Lord British is apparently present as a character — with Richard Garriott’s permission — in the game.

You can grab a copy of the game at its website, or via the newly-minted project entry here at the Codex.