[whswhs]

When I ran Inhuman Space, nearly all the cosmic horrors were Transhuman Technology Gone Wrong. (The backstory of the PCs was that most of them had been together years earlier as a cleanup team for Pacific War bioweapons.) But I did run them into an alien threat, which was a lot like the "protomolecule" in The Expanse: a living metal nanotech entity that had entered the solar system via interstellar orbit and then falling into circumjovian orbit, where it was found by a research ship. It couldn't digest organics but it started eating the PCs' ship. . . .