[ERF] Harvester Drones: Growth

FLEET DEVELOPMENT & DEPARTURE
The vast majority of harvester drones exist in fleets wandering the Scuttler Slice. Their life cycle traditionally begins with a single maintenance drone, often times left stranded after its fleet has abandoned it or been destroyed. Given sufficient time and resources, the drone will eventually grow into a fully-fledged, self-sufficient harvester fleet - and promptly depart for the Lost Reach. The rise and flight of a harvester fleet can take on many forms and follow many different paths, but nearly all begin and end the same way.

Beginning from a single maintenance flyer, harvester instinct naturally compels the individual drone to collect resources. Isolated drones often favor dense debris fields and derelicts, where hiding places are plentiful and resources are close by. These resources are devoted to the task of constructing additional harvesters, who, in turn, follow the same pattern. In time, the growing swarm will eventually decide to construct a larger manufacturing facility to support their operations. While the requirements often vary based on local conditions, this most often occurs when there are at least ten drones in the swarm. Drones during this phase will actively avoid combat, even at cost to their swarm.

In some cases, a garbage hauler processing center will be co-opted through a massed network attack. In others, the harvesters will construct a mining platform on a resource-rich asteroid or scrapball, which will eventually develop itself into a factory. Regardless of their methods, the manufacturing facility will grow to produce larger, more advanced harvesters. In turn, the new harvesters will assist in establishing additional industrial capacity in the local area.

Eventually, the facilities will be uprooted, combined, and converted into a light droneship. On exhausting the resources in their immediate area, the harvesters will board the droneship and depart. Regions especially rich in resources may lead to the construction of additional droneships, or expansion of their original droneship. Once the harvesters have left their original location, they will continue to travel until they can discover another resource opportunity. This process will repeat until an arbitrary threshold of fleet strength has been met. Harvesters during this phase avoid direct conflict as much as possible.

Once the fleet has grown large enough, it will wander permanently. Stops are made only to harvest convenient derelicts, or to collect salvage from garbage hauler facilities. During this time, the harvester fleet will openly attack non-harvester ships and stations it can safely overwhelm. The fleet's primary goal at this time is to move to support other harvesters in combat or salvage operations. This shows many prominent parallels to Space Looney operations; harvester fleets may absorb fledgling swarms or join larger fleets, but often attempt to retain their autonomy to increase coverage across orbit.

Upon the construction of a heavy droneship, the harvester fleet will stockpile resources and supporting drones. Once the fleet is full, it will attempt to push past the graveyard orbit to the Lost Reach. During this time, it will completely disregard salvage opportunities and avoid combat. Fleets that are attacked or encounter other difficulties will only divert to rescue struggling or disabled ships. Even individual drones will continue their attempt to leave Set's orbit should their fleet be destroyed. Harvester fleets do not return from the Lost Reach, and are permanently lost whenever Set jumps.

This behavior goes without explanation, and research into the subject has yet to discover its cause. Leading theories suggest that larger harvester fleets may believe themselves too large for the planet's orbit. They therefore move to an unpopulated planet, to afford smaller harvester fleets room to grow. Other theories suggest that the harvesters are responding to distress calls from fleets lost to Set's jumps. So far, no evidence has surfaced to support any single hypothesis. Due to the distances involved in interplanetary travel, it is believed that harvester fleets leaving Set are eventually disabled by fuel shortages.

COLONY DEVELOPMENT & TERMINAL BURROWING
On Set's surface, its satellites, or large asteroids in the Scuttler Slice, harvester colonies take on a subterranean approach. They tunnel deep into the underground, dig ever-more-complex mining caverns, and eventually disappear into the depths altogether. Most colonies begin as nothing more than a handful of maintenance drones and end as abandoned tunnel networks. Just as fleets above, grounded harvesters can face - and overcome - an immense variety of challenges.

At its most basic, a colony begins with a handful of drones forced to inhabit one of Set's moons or the planet itself. In some cases, the drones may have instead elected to bed down on a large asteroid in order to conduct extensive mining operations. In either case, the drones go to work digging and collecting resources to construct a stationary mining structure. This structure is meant to serve as an excavation tool, mineshaft entrance, and a small-scale manufacturing center all in one.

The drones assist the structure in mining until the central shaft has been carved deep enough for them to safely inhabit it. Afterwards, the structure is dismantled and reassembled deeper into the mineshaft. From there, the drones begin production of additional drones and additional mining structures. Some of these structures are assembled on the surface to create additional mineshafts. Others are emplaced underground to continue subsurface mining operations. Larger, more elaborate tunnels are excavated during this time to eventually serve as larger, more elaborate manufacturing facilities.

This process continues for some time until the colony has reached sufficient industrial capacity to begin regular production of utility drones. At this point, surface production facilities are established. Overland expansion escalates significantly. Underground activity slows, but continues to expand. Some limited communications infrastructure is developed during this time, primarily for the purpose of defensive cyberwarfare attacks. Construction of major industrial facilities marks the successful maturity of the colony.

It is at this stage that most lunar and asteroid colonies dislodge themselves and convert most of their resources into droneships. Some asteroid colonies may remain in this stage until they can completely consume their parent asteroid. For terrestrial colonies, growth continues, and steadily begins to shift away from surface expansion. The underground becomes the primary focus of the colony. Mining tunnels grow in depth, intricacy, and instability. Sinkholes and similar phenomena steadily become more common and more complex as harvester activity continues.

Terrestrial colonies continue this trend until surface activity stops altogether. The colony shifts focus entirely towards digging deeper into the planet, with production facilities trailing behind their mining tunnels. This stage of the colony's development continues indefinitely. The harvesters continue to dig and build downwards, salvaging old structures behind them as they push deeper underground. Eventually, the harvesters disappear entirely. For this reason, the conclusion of a colony's development is generally regarded as "terminal burrowing", in reference to hypothermic behavior of the same name.

As with fleet departures, the cause behind terminal burrowing in harvesters is unknown. Terrestrial harvesters rarely build droneships, and their downward spiral is unlike any other facet of harvester behavior. Some harvester colonies have been observed still digging inside the Great Filter, after descending from Set's surface. Abandoned harvester tunnels have been found leading as deep as the Underworld. Leftover tunnel networks often serve as homes for subterranean towns, underground nomads, and cave-stalking monsters. To date, there is absolutely no substantiated explanation for this activity. No single theory has risen above the rest.