The other worlds, too, had not escaped. All at one point had been on Lilith, and they’d taken the snake back home with them to the other three planets. Finally, using remote probes, the combined scientific studies of a major lab cruiser off the planets found the culprit—an alien organism like nothing else ever seen.
Submicroscopic, it lived in colonies within the cells. Though not intelligent in any human sense, it did seem to be able to enforce an amazing set of rules on an entire planet, given an incredible capacity for evolving to meet any threat to the ecosystem and subdue it. Living an entire life span in only three to five minutes, its ability to evolve into whatever was necessary to obey its genetic coding—to keep things as they were—was strong. Within six months the organism had evolved enough to take care of the human interlopers, attacking and corroding all non-native materials and permeating and establishing a symbiotic relationship with the humans.
The other planets, however, held different fates for intruders. Different atmospheric balances, gravitational forces, radiation intensities—all sorts of differences existed on each, so this bug, this submicroscopic life form, could not change those worlds into Lilith. Instead, the organism changed. On Medusa it adapted the host organism to the new environment, striking a balance that way. On Charon and Cerberus it struck a balance within its hosts that was to its liking but which caused bizarre side effects in those hosts.