The Karibna were formerly advanced race that fell from polluting their planet and degenerated into a race of body harvesters.
The Karibna were once a proud, technologically advanced race. But eventually, as so many have before them, they crumbled under the weight of their own advances. Their planet's resources were completely consumed. With the surface of the planet uninhabitable and dangerous, an enormous space station was built to relocate the population. Their advanced technology kept them alive long after their planet had died. But, over generations, their resources dwindled. Their great knowledge was slowly forgotten and eventually the only resources they had left on their space - were themselves. With organic matter the only thing left to them, they harnessed their own bio-energy for power and started to consume themselves to farm their own race.
One day, a peaceful alien race visited the Karibna and tried to reach out to them in offer of friendship and knowledge; however, the Karibna had already lost their sense of morality and slaughtered the peaceful race. One of the aliens, in desperation, operated a beacon to contact its brethern for help but they too were overran. While the Karibna's own technological knowledge was lost to them, they still had the ability to steal their victim's. They used that surviving alien, stripping him to a mere brain so they could operate and used him to control sentient ships. Knowing their ships would attract sentient beings, the Karibna forced the alien to send them into space, turning them into harvesters. When they receive the signal, that a harvester is full, they activate the beacon for its return to literally harvest any unsuspecting races and incorporating into the station.
The Authority's Carrier was one of these harvesters and was likewise taken to the Karibna's station and taking its passengers, including The Authority. Fortunately, some members of The Authority escape from the Karibna's grasp and encountered the brain that was controlling the ships. The Authority euthanize the brain and freeing the Carrier and the other ships, allowing The Authority to fight back against the Karibna and freeing their untold number of prisoners. Through the actions of Jack Hawksmoor, the Karibna's station fell out of orbit and crash into their planet, killing a large majority of the Karibna and ending their genocide. Although, a fair number of Karibna survived and chased after The Authority; however, the vengeful Karibna were instead lure into confronting the predatory entity known as Mondregon, which then begins to destroying whatever left of the Karibna.