Sirens
The Sirens are a psychic Xenos species, that can gain control of those who fall prey to their mesmeric abilities.[1b]
Description
They are small Xenos, that have numerous tentacles and cluster of orbs for eyes, which have a terrible intelligence within them. The Sirens attack with their psychic abilities and cast out their senses to find the minds of their prey. Once they sense one, the Xenos will use their mesmeric abilities, which strike directly at their victims' minds. This will feel like a hundred tiny worms are crawling through them, before this gives way to warmth and relaxation spreading through the victims' bodies. What comes next is the most dangers part of the Sirens' psychic attack, as their victims' brains are shown tempting visions. The parts of the brain that can analyse and know they are being shown false visions are then disabled, as the victims are completely overwhelmed by the Xenos' psychic might. These tempting visions vary depending on the victim and could for example transport them back to their childhood. Regardless of what is shown, however, the visions are used to convince the Sirens' prey to come to them, and could use the form of a family member to do so.[1b]
If the victims are completely enraptured, they will do so and will attack anyone who tries to stop them. It is not known what the Sirens do to their victims when physical contact is made, but the usual result is their victims become zombie-like creatures known as the Mindless. These are psychically controlled by the Xenos, which causes the Mindless to mumble and drool, while having trembling and erratic motions, along with stumbling movements. It will also remove the Mindless' abilities to feel pain or fear and the Sirens will send them stumbling at their foes, heedless of the damage they take or losses they suffer. The Mindless will continue to advance regardless of the damage they take, unless their bodies are taken apart. Even the loss of legs will not prevent them from trying to come into physical range of the foes of their Xenos masters. Should they do so, the Mindless become extremely deadly, not only because they can not feel pain, but also because the Sirens have given them unnatural strength as well. This allows the Mindless to easily beat the Sirens' foes to death with their never tiring, flailing fists. A direct powerful blow can even kill on impact, while then sending their foe's body hurtling through the air.[1b]
It is not known, how close the Sirens must be to direct the Mindless, as they are rarely seen, but some of their victims serve as transports for the Xenos. The Sirens will take direct control of them, by clinging to the back of the victim's neck and then wrapping their tentacles around them. These tentacles will then burrow into the victim's body, where they will writhe continually, while the Siren is connected to their host. These Mindless are so under the Sirens control, that while the Xenos lack facial features, their anger can become displayed on their hosts' faces.[1b]
The only known way to prevent a victim from falling into the Sirens' control, is for them break free while the Xenos' are initially showing them tempting visions. Imperial survivors have noted that constant physical pain is enough to break free from the visions and prayers to the Emperor will do so as well. Even while enraptured by the Xenos' visions, their subconscious minds will sometimes carry out these actions and if is done before they make contact with the Sirens, the Imperials will be able to free themselves from the Sirens' grasp.[1b]
History
The Sirens are currently invading the Imperial world Darwin II[1a] and several Regiments of Catachan Jungle Fighters, and a Jurian Regiment have been sent to combat them. However due to the Xenos's psychic abilities, many of the Regiments' Guardsmen have fallen under the Sirens' control and they are now being used to fight their fellow Imperials.[1b]
