Poison Headcrab

The poison headcrab (also known as black headcrabs and venom headcrabs), is identified by its dark sage green color skin (sometimes with a wet shine) and thick hairs on the joints of its inward bending legs. To distinguish it further it has white bands that encircle its knee joints. Unlike the fast headcrabs, poison headcrab have beaks on their underside like normal headcrabs. It also makes a distinctly sinister chirp at range and a hissing/rattling similar to that of a rattlesnake's tail when it detects a viable host. According to Half-Life 2: Raising The Bar, the development team noticed that upon hearing the poison headcrab's sound playtesters would frantically start looking around for the poison headcrab so they could destroy it, regardless of any other present dangers. Poison headcrabs move slowly and cautiously when maneuvering but will leap with incredible speed and height with an angry squeal when it has a clear line of sight to the player, and run around frantically when shot at. To further add to their fearsome nature, the dorsal markings of the poison headcrab are similar to that of a species of orb-weaving spider, Araneus diadematus. At walking pace, the poison headcrab is the slowest of the headcrabs, but will run much faster than a normal headcrab if injured.



A poison headcrab's neurotoxin is extremely powerful and hazardous to non-hosts delivered from four fangs on its "mouth". In gameplay it reduces the player's health to 1% immediately upon contact regardless of the current health amount (but health slowly recovers if they remain away from harm for a period of time, due to the HEV suit quickly providing an antidote). As the poison headcrab's only method of attack is by its poison and not from direct physical damage, there is no way for it, or even an army of them, to kill the player outright. However, this does make the player extremely vulnerable to enemies which are in the vicinity of poison headcrabs, as a player attacked by a poison headcrab is unable to resist even the slightest damage until they recover. Poison headcrab attacks will, however, drain the player's HEV suit power.