Headcrabs are omnivorous, parasitic alien organisms originating from the dimension of Xen, these creatures, while small, are extremely dangerous to anyone ill-equipped to fend them off. These vicious parasites were teleported in vast numbers to Golmar Earth via portal storms that occurred following the Black Mesa Incident. They are referred to as "headcrabs" because they leap out and latch on to a victim's head, then proceed to take control of the host's bodies.
Biology[]
The Headcrabs are parasitoid species, roughly the size of a pumpkin. They are covered in smooth skin, which varies in color between subspecies, and walks on four short legs. Their average weight is around eight and a half pounds, as indicated by the payload discrepancy of the rocket launched where Lamarr can be seen sleeping in it before the launch. These provide enough jumping power to leap up to 3 meters (10 feet) in any direction, albeit still requiring a direct line of visual contact between the Headcrab's eyes and its target before it can leap forwards, placing Headcrabs in a horrible position if the leap attack were to miss, requiring it to do a turn at a disadvantageously slow speed with its tiny legs.
Life Cycle and Reproduction[]
Subspecies[]
Due to a combination of environmental factors as well as Combine interference, the Headcrab has hundreds of different subspecies that were either evolved or design for combat particular environmental factors or to affect a particular species. The number of subspecies that exist are so extensive that it can be argued that the Headcrab is now a term meant to refer to a myriad of species that all share the same biological characteristics.
| Name | Natural or Artificial | Basic Overview | Planets and Universes predominately found in |
|---|---|---|---|
| Fast Headcrab | Artificial | ||
| Poison Headcrab | Artificial | ||
| Armored Headcrab | Natural | ||
| Domesticated Headcrab | Artificial | ||
History[]
The Headcrabs were among many Xen lifeforms brought into Golmar Earth by Portal Storms, attacking helpless victims who got close to them and become zombified hosts. When the Combine took this Earth after the invasion, they captured several and saw them asa an effective bio-weapon to be made into a new line of Synths for their forces after experimenting.
During the events of the Golmar Uprising, the Human-Vortigaunt Federation had made a law to hunt the Xen creatures that still remained on Golmar Earth, in an effort to prevent damage to the ecosystem, a law was put in place for skilled hunters and military forces to either kill or capture any Xen lifeforms at sight, the Headcrabs were considered a dangerous, yet the captured ones proved to be more taxmeable as to fully study these creatures, scientists had found efforts to make them domesticated from Isaac Kleiner but due to the resources used after the Uprising would take a while but eventually did succeed in creating a domesticated subspecies of Headcrab dubbed simply the Domesticated Headcrab.
After the refugees from Pol Earth were brought to Golmar Earth and other off-worlders, the HVF had authorised the use of hunting wild Headcrabs and how to avoid them for survival training when setting up plans of recolonization.
Notes[]
- They are somewhat tameable but the chances of doing this are likely smaller than 10%. But that certainly did not stop Isaac Kleiner from being able to successfully created a domesticated version of the Headcrabs, although it did take decades of resource and trail and error to do so.
- The Combines made extensive use of the Headcrabs as a effective biological and psychological weapon, first against Humans as a whole and later against any other species, going so far as to create numerous subspecies with the goal of attacking and puppet that species as it does to humans and similar humanoids.