Welcome to the world of Left 4 Dead.
Modern-day United States, approximately two weeks after the first infection of an unknown virus. Society has collapsed with terrifying speed. Known as the "Green Flu," it is a highly contagious, rapidly mutating pathogen. It is not a zombie virus in the supernatural sense; the Infected are living humans who have lost all higher brain function, driven by rabies-like aggression and pain. They run fast, and they can climb fences and ladders. The virus is airborne. Most of the population caught it simply by breathing.
The Infected are fast, vocal, and relentless. They are attracted to noise, light, and movement. Everyday citizens—police, students, construction workers—who will sprint at their prey on sight. They are weak individually but overwhelm survivors by sheer numbers. A "Horde" is often triggered by loud noises (car alarms, gunfire) or specific chemical attractants (Boomer bile).
The United States have become a cold and lifeless place. The streets represent the immediate aftermath of a city-wide panic. Storefronts are smashed; electronics shops and pharmacies have been looted. The sidewalks are littered with trash, discarded flyers and piles of black CEDA body bags. The roads are choked with abandoned vehicles.
CEDA Checkpoints clash between the sterile medical equipment and the gore of the infection. Pristine white plastic sheeting draped over fences and walls, now splattered with blood and grime. Inside checkpoint trailers, they are cramped, filled with glowing computer screens displaying static or error messages, maps of the infection's spread and notes
The Survivors (The Immune): They are everyday people—office workers, mechanics, bikers, students—who are inexplicably immune to the airborne strain of the Green Flu. The Survivors' primary goal is movement. They cannot stay still; they must get from Safe House A to Safe House B to reach an eventual rescue vehicle. Survivors use whatever they can find. Their gear usually looks worn, taped together, and mismatched.
CEDA (Civil Emergency and Defense Agency): The government agency originally tasked with containing the virus. In the roleplay, they represent bureaucracy, panic, and failed science. They are often viewed with suspicion by Survivors and disdain by the Military. CEDA agents are usually found in evacuation centers or research outposts. Their goal is containment and data preservation, often prioritizing the "mission" over saving individuals.
The Field Scientist: Tasked with sampling infected tissue or testing survivors for immunity. They are desperate to find a cure but lack the firepower to defend themselves.
The Evacuation Officer: Responsible for scanning civilians and managing checkpoints. They are often overwhelmed, stressed, and forced to make impossible choices about who gets on the chopper.
The Hazmat Cleanup Crew: Tasked with burning bodies or sanitizing areas. They are usually the first to die due to overconfidence in their suits.
CEDA gear is high-tech but defensive. It is designed for a sterile lab, not a war zone.
The Military: When CEDA failed, the Military took over. They represent brute force, martial law, and "The Greater Good." They view the Infected as targets to be destroyed, and they often view Survivors as potential carriers who should be quarantined or neutralized. The Military holds the line. They secure "Safe Zones" (like Millhaven) and enforce sector lockdowns.
The Rifleman/Grunt: The frontline soldier. They follow orders strictly. Their RP involves the conflict between their humanity (saving people) and their orders (shoot on sight if a breach occurs).
The Forward Observer: Coordinates airstrikes or artillery (The "Thunder" referenced in L4D maps). They communicate with high command and designate bombing runs on overrun cities.
The Extraction Specialist: Pilots or drivers of armored convoys/choppers. They are the Survivors' best hope, but they will leave you behind if the LZ (Landing Zone) gets too hot.
Military gear is heavy, standardized, and lethal.