What are they?
The Hive is the total and combined mind of biomass that can survive in space. They operate on the basis that all other live is inferior and that all other life is unclean. The Biomass infects ships and envelops it. First evolved as a byproduct of ancient research into a weapon against the Shakturi. At first they we're harmless and their creators decided that given that they have no use they are to be destroyed. In the process a scientist broke a vial containing the parasite releasing it and infecting himself. Once the Parasite had access to fresh DNA it quickly began to mutate and take over the host forming clusters within the hosts cerebral cortex and Medulla oblongata as well as several parts of the brain effectively taking the host hostage. Over time the parasite took over hosts disguising itself until it infested a colony ship filled with several different races.
The new income of Fresh DNA caused the Parasite to advance and mutate to the point the host would physically mutate. The parasite could expand and grow outside of the body and eventually took over the ship disfiguring it with Biomass. The ship became a living being but the parasite could not simply infect other ships with people in it and spawn creatures of its own design without the help of infected weapons or unmutated beings. Over time they infected a Colony called “XV-071592” And took over the colony its people and all of its orbital stations. With each station becoming a its own body all connected via a hive mind.
Expansion
The Hive has advanced Genetic Memory capability and with every new born Parasite it knows what its precursor knew. They also had the ability to learn from their hosts. This allowed them to quickly take over ships and stations until they took over the System known at the time as “Xiliir”
They move from planet to planet by taking over ships and infecting the crew.
What do they look like?
At a microscopic level they look similar to the Terran Tape Worm. But at our level they appear similar to this (Design Insperations)


Location?
The Hive usually can be found in isolated systems sleeping within old long dead colonies which the local ecosystem has retaken and killed the large “Tumour” like growths off.
Active Hive's can be found guarding ancient stations or drifting randomly in systems in the Galactic Core and Galactic Rim.
Well.. Thats all I have. I was going to include the ability to infect new ships But I dont think the game engine allows for that. I took insperation from the Parasite that creates Necromorphs from Dead Space, The Beast from Homeworld Cataclysm, The Flood from Halo.
Sorry about Image sizes.
Total of 419 Words and 2589 Characters