Typically, the invasion of the larvae results in major depopulations and mass extinctions, combined with serious climatic and ecological damage.
Powered by gravities, the spacecraft built by the larvae lift into space—with luck, before the planet’s ecosphere is utterly ruined. With one larva aboard each vehicle, the spacecraft can be compared to hermit crab shells—temporary homes to be used as long as they fit. If the larva dies or grows too large for the craft, the vehicle will be cannibalized for parts. Nine-tenths of the larvae die upon arrival in space. Their corpses serve as sustenance for the survivors.
Each surviving larva battles it out with its rivals to amass as many of the dead bodies and abandoned spacecraft as possible. Eventually, thirty or forty thousand massive creatures, in the pupa phase, are left. Each consists of the components of several derelict spacecraft and one individual pupa that has fed on the bodies of its littermates. Ship and creature merge with each other and become indistinguishable. Each is the size of a small asteroid, being several kilometers across with proportionate mass.
One or two pupae land on the nearest non-life-bearing world and burrow into it. Should a pupa survive this effort, the machine parts of the creature will build and breed a Caller Ring. A Caller Ring is buried deep in the Earth’s Moon.
However, most pupae enter a chrysalis phase, becoming dormant, their outer skins hardening into the consistency of rock. Thus, not only are they the size of asteroids, they precisely resemble them. These creatures, which become Worldeaters, go into hiding. In Earth’s Solar System, they hid in the Asteroid Belt and the Oort Cloud. At this stage, all the Charonian creatures, both living and robotic, are dormant, waiting for a signal.
A signal to the Caller Ring stimulates a new phase of great activity. The Caller Ring can be activated in one of two ways: by signal from the home Dyson Sphere, indicating that the Sphere has a sufficient surplus of energy to assist in the construction of a daughter sphere; or, by outside interference: pulsed gravity waves generated by some other cause—for example, gravity experiments performed by an intelligent race.
When the Caller Ring detects a burst of controlled gravitic energy, it performs its basic function—opening a gravitic contact, a Virtual Black Hole transit pair, linking it to its home Dyson Sphere. The Caller Ring then sends a pulsed-gravity-wave signal to the Worldeater chrysalides sleeping in the star system.
Linked to the home Dyson Sphere, the Caller Ring attempts to get the life-bearing world out of harm’s way by shifting it to the artificial star system surrounding the home Sphere. If the Sphere initiated the call, or if it has at least some surplus of energy available, it permits the transit to take place. Earth’s sudden arrival is not the first unplanned grab of a world—the Dyson Sphere knows how to handle such things.
As soon as possible, the Sphere shifts an Anchor black hole through the temporary Virtual Black Hole, providing a more powerful and stable link to the home Sphere.
The Multisystem of habitable worlds orbiting the home Dyson Sphere can be thought of as a field lying fallow. The Charonians accumulate life-supporting planets that can be sent to where they are needed.
If a seedship has visited several unsuitable solar systems and is near the end of its operational life when it arrives at yet another lifeless system, it can call the home Dyson Sphere and give up the last of its energy to have one of the stockpiled worlds shifted to an otherwise suitable solar system. Replaced by a new seedship shifted in with the new world, the life cycle can then proceed.
The Dyson Sphere begins to beam energy through the Caller Ring. The awakening chrysalides emerge from their long sleep as adult Worldeaters. Their robotic components link with the Caller Ring and begin to absorb power. The Worldeaters head toward the major worlds of the solar system and start ripping them to shreds, forming them into the materials needed to form a new Dyson Sphere. Their work can take hundreds or thousands of years, but at its end, a new Sphere is ready, able to breed and build its own seedships and begin construction of its own empire of captive worlds.