"We are the Borg. You will be assimilated. Resistance is futile."– Borg Collective, 1420 N.E
The Borg (Second Human Empire name Oiki'mooi Xikki'llooi) were a pseudo-species of cybernetic beings, or cyborgs, from the Delta Quadrant. They are very similar to the Dark Collective in the terms of cybernetic beings. No single individual truly existed within the Borg Collective (with the possible sole exception of the Borg Queen), as all Borg were linked into a hive mind. Their ultimate goal was the attainment of 'perfection' through the forcible assimilation of diverse sentient species, technologies, and knowledge. As a result, the Borg were among the most powerful and feared powers in the multiverse, without really being a true species at all.
The physiology of each Borg drone varied according to the species from which it was assimilated. Drones were typically humanoid, although the Collective demonstrated a willingness to assimilate non-humanoid lifeforms.
Upon assimilation, a drone ceased to grow body hair and developed an ashen, grayish skin coloration, ignoring original skin pigmentation. Cybernetic implants were either surgically attached to the body or grown internally by nanoprobes injected into the bloodstream and can cause severe skin irritation. The nature of these implants varied from drone to drone, depending on its intended function, but basic nodes of interlink for communications with the Collective and myo-neural cortical array to control movements, were implemented in every drone. In most cases an eye would be replaced with an eyepiece that improved vision and an arm would be amputated altogether to make room for a functional prosthetic; in tactical drones a weapon would be included, and some drones had medical tools built in. The implants of a fully assimilated drone allowed it to function for extended periods without shelter, food, water, or even air. It could even survive in the vacuum of space. A drone's only requirement was a supply of energy to maintain the implants that in turn maintained its biological functions. This energy was supplied during regeneration cycles within a Borg alcove. Upon receiving damage, a drone would return to the alcove for assessment of the damage. Severely damaged drones were disassembled and scavenged for reusable parts.
Borg infants were not accepted to the collective until they matured to a certain age. Until reaching this age, assimilated infants and youths were placed inside maturation chambers.