c5a1. The Nihilanth is the supreme leader of the alien forces in Xen. An ancient being who is thought to be the last of their race, the Nihilanth serves as the main antagonist and final boss of Half-Life, responsible for spearheading the invasion of Earth during the Black Mesa Incident . A refugee fleeing the terrible power of the Combine, the There's been a lot of Half-Life 2 talk lately, what with Marc Laidlaw creatively writing some gender-swapped fan fiction that revealed his vision for the missing Episode 3 and Lever Softworks Walkthrough By IGN-GameGuides , Andrew Eisen , IGN-Cheats , +287 more updated Sep 11, 2012 Greetings and welcome to the walkthrough of our Half-Life 2: Episode Two Wiki Guide! 2VHQ4C.