Ringworld. And maybe a little Runequest as a cameo.
Ringworld was an RPG based on the Larry Niven novels set his his Known Space universe on a huge ribbon-like structure orbiting a star. Halo old-school. At the time of its publishing, two of the four Ringworld novels were out, and I don't know if the information here would jive with what Niven eventually did. I remember this game primarily from it being in the TSR Library, along with Elfquest, which is a related game.
Ringworld is a good representative of a product for a universal game system. This was a holy grail for a while, and I suppose still is. The big practitioner has been GURPS, but the Basic Roleplaying System (BRP) from Chaosium has been another contender. Other games related through the BRP include the indominable Call of Cthulhu, the aforementioned Runequest, Superworld, Elric, Hawkmoon, and Pendragon. It is a pretty impressive family tree, and, looking at them over the years, you can see that they shared the same earthy loam. While GURPs presented itself a GURPS (name of genre or license), BRP presented itself as Name of Genre or Licence (using BRP).
The trouble with universal games is a basic challenge - which is more important, the mechanics or the world? A world (or license) has different virtues, strengths, and requirements, so bending the world to fit the Procrustean bed of set mechanics is a bad fit. However, a universal system has the advantage that, once someone understands product A, it is a shorter leap to product B, which has a similar system. And the ultimate goal of such systems, in theory, is the ability to take characters from World X and put them in World Y.
BRP, a creature of its age, creates entire systems which are glued on or jettisoned as appropriate for the game. A pretty smart move. Call of Cthulhu has its insanity, Superworld its super powers, and I think Pendragon pulled up everything but the floorboards. Its game family is so diverse that it makes world-hopping a little more problematic, but you can see the connecting tissue.
As for the Ringworld game product, only the cover and a few memories remain. I don't remember a whole lot of additional mechanics, or if those mechanics served the purpose of supporting the world it was supposed to portray. I do remember that the the data on the universe felt a little light - not a lot of parallel support (as opposed to West End's Star Wars, which practically ran lateral development and continuity for LucasFilm for many years), and I don't remember any mysteries being resolved. Further, the scope of the Ringwold was so big (the planet Earth in the novels was portrayed as a map on an island at a 1:1 scale, that the place ultimately had the problem of many "super-dungeons" there was so much there that it was hard to embrace it all.
But it and similar universal systems were a major step in RPG development. In trying to create a system that could be plugged into several genres, it helped push the entire concept of licensing, where turnaround time was vital and striking while the iron/movie/book was hot was ideal. And that's good enough for R.
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