In the AvP EU there are some secret organisations, like the OWLF (later renamed as Stargazers), the Loki from Original Sin, or the X Group from AvP: Hunters Planet. We don't know what is the X Group's true name, and only have a small information about them. Runed by a group of independent freethinkers, who are everywhere, even in the Weyland-Yutani Corp. The Group's common goal is to defend the galaxy from the greedy humans, who are robbing the planets (mining), or just simply destroys complete races to make a colony more safer. And there are nobody, who can stop them... except the X Group.
In the novel, AvP: Hunters Planet, the X Group made Attila, a synthetic, owned by Machiko Noguchi. Attila himself didn't know what is he capable of (like shoot laser with his mouth, driving helicopter or speak with the Yautjas). Machiko and Attila succesfully destroyed the Xenoborg lab, ending Livermore's world domination plans. And pretty much thats all we know about the X Group, they never ever made another appearence... but a man could theorize, what if they returned more times, just not named?
Right in the Female War book adaptation, we have a bit os backstory of who made Ripley (the synthetic). In her dream, we can see Bishop in the time, when Ripley gave birth to Amanda. Given that this synthetic Ripley don't have any memory after the events of Aliens (meaning, that she didn't remember the Fury-161 incident), we can assume, that in her dream Michael Weyland featured, not Bishop. Also Bishop is made after his creator, Weyland, who is a brilliant mind in the synthetic industry. Also, Ripley knew about Orona's bomb, exactly knew where she can find them and how to activete them. I know, what are you thinking, if Michael is her creator than the W-Y why didn't supported her with hundreds of soldiers, Berserker Units, etc? Well, because what if the W-Y didn't know about Ripley, and Michael was a member of the X Group? In the Colonial Marines game and it's DLC (Stasis Interrupted) Michael presented as an evil man, but what if he just played that roll, or become a good guy after 2179?
Also, in the comic Aliens: Defiance, Davis 01 is very suspicious. We know, that he become rogue, who's goal to prevent the W-Y's plan to capteure an Alien. But... how he ended up in the combat android group, sent into the Europa in 2137 december? Davis knew, that the ship is infested by Aliens, but he is just a synthetic, he cannot requst himself into this mission. Someone in the W-Y's higher ups must helped him to get into the group. Also Davis 01's body is more stonger (he literally single handedly destroyed half a dozen synthetic, while suffered multiple gun shots), this is because he was a commander, or the X Group made him stronger. Also Davis 01 is much smarter than an avarage combat android, capable of learn things very fast (just like Attila from Hunters Planet). In my opinion it would be cool to see, that in the upcoming novels and comics Zula and Amandra Ripley work for this X Group.
Before I end this topic, I would like to theorize about the Earthsavers from Covenant: Origins. Just like the X Group, the Savers are everywhere, even inside the W-Y. Their goal is to save humanity from the Aliens, by sabotaging the Covenant's start. At the end of the novel, the W-Y pretty much destroyed this organisation, their prophet, Duncan Fields and most of the Earthsavers staff is captured. Some minor cell survived the purging, but they become a minor threath. What if the Earthsavers is the predecessors of the X Group? What if Duncan Fields convinced some W-Y employees, or the remaning cells created a new organisation with new goals.
