The deadly and horrific Xenomorphs of the Alien Universe once bred humans like livestock for the continued survival of their hive. A Xenomorph hive has oftentimes been depicted as a mucus-laden cavern where Xenomorphs take humans to be impregnated with more of their kind. In one iteration, there weren’t enough hosts surrounding a Xenomorph hive to ensure its survival, so the vile aliens used the handful of humans they had and tried to breed them with the idea of making more hosts and in turn, more Xenomorphs.
In Aliens: Labyrinth by Jim Woodring and Kilian Plunkett, a mad scientist named Dr. Paul Church is experimenting on Xenomorphs after surviving a horrific past experience that made him obsessed with the creatures. In the third issue of the series, Church recounts his experience with the Xenomorphs that led him down his current path. Years ago when Church was a young man, he along with his family and a handful of other crew members traveled to a distant planet where a previous crew was reported lost. Upon their arrival, they are attacked by a horde of Xenomorphs and were taken to their hive where a fate worse than death awaited them.
After an initial fight broke out while inside the hive, the humans were split up and Church was taken to a deeper region within where he witnessed horrors beyond his comprehension. The bodies of the previous crew members that were captured were melted together and strung up on the ceiling of the hive, with most of them still clinging to their torturous lives. Church was pinned to a wall alongside them, and after a few days of being ignored by the Xenomorphs, the aliens returned, snatched a piece of meat from the mutilated crew, and fed it to Church in order to keep him alive. The Xenomorphs then brought Church to a female member of his crew who was missing her arms and legs, and the Xenomorphs tried to force Church to mate with the woman who he soon learned was his own mother. Instead, Church killed his mother, a move that angered the Xenomorphs but not enough for them to kill him in retaliation.
Eventually, the Xenomorphs were somewhat successful in breeding the humans, though the child products were seemingly infected with alien DNA and didn’t survive long after their birth. The most shocking revelation from the series is that the Xenomorphs were aware of their impending doom if they didn’t procreate and understood human biology well enough to keep the ones they had alive and even breed them to make more, though they were overall unsuccessful in that effort in terms of making viable hosts.
The Xenomorph species is constantly evolving within the Alien mythos, with the first incarnation of a hive appearing in the film Aliens where the creatures were depicted somewhat like cosmic ants. In Alien: Labyrinth, the Xenomorphs are much like people in their intelligence, using the resources they had to try and maintain their survival by keeping people alive, and even breeding them rather than mindlessly killing or infecting them with an embryo. One Alien story depicted the Xenomorphs treating humans like livestock in their effort to survive which is arguably one of the greatest and most disturbing examples of their higher intelligence.