Headcrabless Zombies image - The Deception mod for Half-Life 2

Gera, a city in the US has been abandoned for five years due to an attack of biological terrorism. The attack was done with a bioweapon developed by engineers commissioned by government. Terrorists sabatoged the weapon, causing a meltdown and destroying most of Gera's population. The city has been quarantined until now. Gera is currently occupied by a small cell of the terrorists responsible. They have been conducting psychokinetic experimenting on humans- creating a clone army and mutating the human genome. The military has been tasked with infiltrating one of these research facilities. Your squad will be dropped on the roof of the research labs in the city hall. It won't be easy- good luck, soldier!