Facehugger

The Facehugger is the second stage in the life cycle of the Xenomorph species. This parasitic organism exists for the sole purpose of implanting a Xenomorph larva into a host. After it has accomplished this task, it dies.

Overview
The Facehugger has a somewhat arachnid appearance, possessing eight spindly legs and a long, sinewy tail. It has no distinct head or obvious sensory organs and appears very skeletal in nature, its legs somewhat resembling bony human fingers. On either side of its body is a bladder-like sac. The underside of the creature sports an orifice resembling a human vagina. From this orifice, a proboscis extends for implanting an embryo into a host.

Despite the skeletal appearance of its limbs, the Facehugger is remarkably strong for a creature of its size. It uses its legs to crawl quickly across terrain and will coil its tail to make powerful leaps as it attempts to latch onto a victim. It will grip a victim's head tightly with its legs, achoring itself in place. The tail will wrap around the victim's neck for additional support ,or to strangle the victim if anyone attempts to remove the creature by force. The sacs on either side of the Facehugger's body act as secondary lungs, providing the host with oxygen while the impregnation process is underway.

Removing a Facehugger is an extremely difficult task. The creature holds onto the victim's face so tightly that forcibly pulling it away will likely result in deathly injury to the host. Surgically removing a Facehugger is equally as challenging as these creatures possess the same acidic blood as other Xenomorphs. Rupturing any part of the Facehugger's blood will result in the expulsion of highly corrosive acid that will rapidly eat through surgical tools and potentially harm the surgeon.

The implantation process of the Facehugger is not yet fully understood. It was originally believed that the proboscis secreted a sedative to paralyze the victim, but it seems that direct skin contact with the parasite's underside is enough to cause paralysis. The implantation process is slow, taking several hours to complete. The proboscis worms its way down the victim's oesophagus before depositing an embryo within. The Xenomorph embryo has never been seen in detail, but it has been theorized that the Facehugger deposits a cluster of mutagenic cells that form a 'placenta' within the victim's chest cavity and construct the Xenomorph larva within it. When the larva has formed sufficiently to begin drawing nutrients from the host, the Facehugger lets go and dies. How the Facehugger knows when to detach is unclear, although it has been theorized that the developing embryo sends a recombinant plasmid pulse to inform the parasite when it is secure.

Variants

 * Royal Facehugger - A Facehugger that is responsible for implanting the embryo of a Xenomorph Queen. This variant can be told apart from standard Facehuggers by the webbing between its legs. Some Royal Facehuggers also feature sharp spines on their backs.
 * Praetorian Facehugger - A Facehugger that is responsible for implanting the embryo of a Praetorian. It has brown, chitinous skin.