Xen

Description
Xen is an alien species that invaded Black Mesa during and after the events of Half-Life, and eventually managed to spread around the world. In the game, it is

shown that Xen was known long before the events of Half-Life.

In-Game
Xen are the focus and antagonists of Headcrab Infection. The species that exist in Headcrab Infection are not limited to just Headcrabs, but every known species aswell, including the plants that exist in the Xen's home-world.

List of Xen
• Headcrab


 * Headcrab Zombie


 * Gonome


 * Mr. Friendly

• Fast Headcrab


 * Fast Headcrab Zombie

• Poison Headcrab


 * Poison Headcrab Zombie


 * Poison Headcrab NPC


 * Poison Zombie NPC

• Gonarch


 * Baby Headcrab

• Bullsquid

• Vortigaunt

• Houndeye

• Alien Grunt

• Snark

• Alien Controller

• Chumtoad

• Xen Tree

• Xen Fungus