I have some ideas for an alternate Traveller Universe that is reachable from the OTU. I imagine you are familiar with the Adventure ANNIC NOVA. The way it was presented, was as something alien an unfamiliar to the OTU, and then it was retconned as a Vilani Starship, its jump drive is quite unique, is doesn't require jump fuel, instead it runs on solar power, but what if it wasn't a jump drive, but a wormhole drive instead?
What if the ANNIC NOVA or something like it originated from a parallel universe instead? One that is one million years in the future, it was built by humans that never developed the jump drive, or did they?
The civilization that built the ringworld, felt that it was important to keep all of humanity in the Solar System, and they were helped in this by the lack of habitable planets, there were no Ancients or extraterrestrial civilizations anywhere in the galaxy, so they build a ringworld to house all the human, and then something happened, civilization collapsed one million years ago.
Genetic engineering, and the vastness of the ringworld produced a number of intelligent species, many derived from human stock, others are uplifted animals such as the vargr and aslan. Some centaurs and merfolk as well. One group of near humans from a newly arisen civilization on the ringworld invented the jump drive, they jumps to other star systems and found a bunch of lifeless balls or rock, gas giants, and icebergs, there was nothing interesting to explore or colonize, and then someone invented the wormhole drive, it was a cousin to the jump drive, but it required a wormhole.
The wormhole connected their universe to the OTU, they jumped and they fell victim to a mysterious disease for which they had no immunity. The PCs find this starship explore it, and while they are on board it jumps right back to the ringworld universe to the ringworld system. It will take them sometime to figure out how to jump back, but in the meantime there is a ringworld to explore.
What if the ANNIC NOVA or something like it originated from a parallel universe instead? One that is one million years in the future, it was built by humans that never developed the jump drive, or did they?
The civilization that built the ringworld, felt that it was important to keep all of humanity in the Solar System, and they were helped in this by the lack of habitable planets, there were no Ancients or extraterrestrial civilizations anywhere in the galaxy, so they build a ringworld to house all the human, and then something happened, civilization collapsed one million years ago.
Genetic engineering, and the vastness of the ringworld produced a number of intelligent species, many derived from human stock, others are uplifted animals such as the vargr and aslan. Some centaurs and merfolk as well. One group of near humans from a newly arisen civilization on the ringworld invented the jump drive, they jumps to other star systems and found a bunch of lifeless balls or rock, gas giants, and icebergs, there was nothing interesting to explore or colonize, and then someone invented the wormhole drive, it was a cousin to the jump drive, but it required a wormhole.
The wormhole connected their universe to the OTU, they jumped and they fell victim to a mysterious disease for which they had no immunity. The PCs find this starship explore it, and while they are on board it jumps right back to the ringworld universe to the ringworld system. It will take them sometime to figure out how to jump back, but in the meantime there is a ringworld to explore.