As regular Xenomorphs in Alien stories tend to get too mainstream, gene splicing is sometimes introduced to create new breeds of often ridiculous Xenomorphs. These new Aliens vary in size and appearance, but still inherit their traits from their hosts. Here is a list of different breeds of Xenomorph hybrids, some born from exotic hosts and others mutated through experimental gene splicing.
White Hybrid Xenomorph
The white hybrids were a new race of creatures created by the rogue AI named Toy in the Aliens vs. Predator: Deadliest of the Species comic series. They inherited the traits of both Xenomorphs, Yautja and humans, but mostly looked like Xenomorphs with white skin. They had acid for blood and still used facehuggers for reproduction. However, they were more intelligent than regular Xenomorphs, some even being able to speak. The white hybrids fought against Big Mama Predator and her allies.
The Newborn was a unique type of Xenomorph only seen in Alien: Resurrection and its related media. It was born from the womb of the Auriga Queen, the cloned Xenomorph extracted from the chest of Ripley 8. The Newborn was huge from the start and was possibly still growing at the end of the movie. Its white skin supports that theory, as chestbursters usually shed their light skin before adulthood. The Newborn expressed great physical strength, but also affection for its presumed mother - Ripley 8. This abnormal Xenomorph never reached adulthood as it was killed by Ripley 8 by sucking it out the hull of the Betty.
The Bug Men were one of the most humanoid Xenomorph hybrids that could talk and carry weapons. They were the result of experimentation with Royal Jelly by Dr. Ernst Kleist, who also famously created the Rogue Alien. The Bug Men were used to further the crazy goals of the mad doctor, kidnapping humans for further experiments and fighting alongside the Xenomorphs. This terrorist cult was featured in the Aliens: Colonial Marines comic book, and were wiped out together with the Colonial Marines squad at the end of the story, when a space station exploded.
Killer Croc Xenomorph
The Killer Croc Alien was born in Gotham City as a result of experimentation on Batman villains by Dr. Fortune. In Batman/Aliens II, she took DNA from prisoners in Arkham Asylum and spliced it when Xenomorph biomatter, trying to create a small army of supersoldiers. While the Joker and Two-Face Xenomorphs were more human-like and easier to control, the Killer Croc Alien was a bad beast that turned against Dr. Fortune and headbit her. Batman took down the monstrosity using his power armor, having experience with fighting crocodile Aliens before in the first Batman/Aliens series.
Mega-City One Queen
Dr. Niels Reinstöt was a gene-splicing, mad-scientist from Mega-City One. Prior to his interaction with any Aliens and Predators, Dr. Reinstöt once claimed he was with Mega-City One's Department of Disease Eradication, and informed City Orphanage BD36-30 that each orphan was to receive a mandatory vaccination against Rad-pox. Dr. Reinstöt created a Predalien and Xenomorph Hybrids via gene-splicing and joined forces with Archbishop Emoji. Finally, he transformed into a Xenomorph Queen when injecting himself with a concoction of Xenomorph DNA he extracted from the skull. You could not make this stuff up. Dr. Reinstöt was included in the Predator vs. Judge Dredd vs. Aliens comic.
The Anchorpoint hybrid was a special breed of Xenomorph that only appeared in the early drafts of William Gibson's Alien 3 script, which was later turned into a comic book. In this story, the Alien lifecycle took a different turn, with eggs emitting spores (similar to what happened in Alien: Covenant) and infecting a host by air. The Alien took several hours to gestate, but instead of being born as a chestburster, it erupted fully grown under the skin of Susan Wells, who was in contact with the spores in a lab accident. The Anchorpoint hybrid otherwise looked similar to a regular Alien Warrior, with a translucent dome and a human skull visible underneath.
The Rogue Xenomorph was a genetic experiment created by Professor Ernst Kleist at Charon Base. It was a creature bigger than all the other Alien types, including the queen. It had reddish skin and spikes all over its body. The Rogue didn't feel much loyalty towards the hive and actually fought the queen Alien. It lost the fight because the queen was able to outsmart it. The Rogue was featured in the Aliens: Rogue comic book and novel, later released as part of the Aliens Omnibus: Volume 3.
Eloise was a female Xenomorph android hybrid with a special relationship with the Xenomorphs. She was created as an experiment and grown in a lab on the planet Sybaris 503. Physically she mostly looks like a human female but had Xenomorph DNA and acid for blood. Her hands were shaped like the claws found on the Xenomorphs and had four Dorsal tubes on the back. She had enhanced speed and strength and was able to telepathically connect with the Xenomorphs who considered her to be part of the hive. She was featured in the Aliens: Purge comic and her adventures continued in the Aliens vs. Predator: Pursuit comic.
The K-Series Xenomorphs were created in a secret Weyland-Yutani biolab on LV-742 by Dr.Kadinsky in the lesser-known Aliens vs. Predator: Extinction video game. There weren't only a few individuals but a whole race of gold and silver-skinned Xenomorphs, including a Queen and Praetorians. The K-Series battled the original strain of Xenomorphs and eventually lost, a situation similar to the Red vs. Black Xenomorph war depicted in Aliens: Genocide. Although a few K-Series hybrids escaped the biolab out into the open, they were hunted down and killed as well.
The scientists at Pala station from Aliens: Infiltrator experimented with Black Goo and accidentally created a new Alpha Warrior Xenomorph, a breed of Alien able to command the others when there is no Queen present. This Albino Alien (named Number Seven) had a telepathic link with the others and instructed them to escape from their holding pens at once, by breaking the weakened glass. Number Seven set up a breeding ground in the cafeteria and herded humans to be infected by facehuggers. After successfully infesting the whole station, it was killed in an explosion near the hangar bay of the station when the last survivors attempted to escape.