Immediately, the sensors on your mote-probe pick up and differentiate two entirely different ecosystems of bacteria locked in a war for survival with each other. For a moment, you attempt to identify which is the native ecology and which is the alien– and then you look to the shore of an approaching continent and see something even more intriguing.
Towers, thin and spindly, dozens of meters tall, rise from the surface by the hundreds, ascend into the low-hanging cloud cover. Where the towers disappear into the mottled haze, massive sacks sag from their sides like clusters of bizarre fruit, each distended pouch huge within loose-hanging, leathery skin. Initial readings find them teeming with bacteria, each thick with a soup of nutrients and strange, almost embryonic shapes that defy definition– and soon you realize that the spires themselves are the source of the cloudcover, that each tower is a living structure, like trees of resin and meat that breathe in the native atmosphere close to the ground and expel the alien contaminants where their spire tips pierce the sky.
How they got here, what their ultimate purpose is, what species seeded them into the mild soil of this little world– there's no way to tell. Their function, their efficiency of design and the sacks hanging ponderously from their sky-stabbing tips point more to engineering than to evolution, but whether the alien tree-towers were grown to terraform, to incubate, to protect or were placed for some other unknowable purpose, you can only speculate.
There are no other relics, no caretakers, no machines, no signs of a delivery system. Nothing but the tree-towers, the billowing, toxic clouds and the beleaguered native land. You could wait in the hopes that whoever planted the spires might return someday, but with no way to know how long you'd be waiting, you decide against it. It's enough to make a notation in the network, to send your observations along for other interested explorers to pick over and speculate on. For you, there are other worlds to visit, other mysteries to uncover, and so you set a return course in the sliver of mind within the mote-probe, spin up your ship's phase drive and prepare to make the jump back to between-space.
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