Like Counter-Strike before it, Valve’s and Turtle Rock Studios’s Left 4 Dead altered the course of multiplayer video games. Its advent in the late 2000s laid the foundation for modern cooperative shooters, placing teamwork at the forefront of a zombie-centric experience that penalized individualistic thinking. Notably, four unique Survivors acted as player avatars teaming up in a world overrun with infected humans, a welcome change of pace at a time when friends had become accustomed to fighting against one another in online shooters.