A team-based first-person zombie shooter first developed by Turtle Rock Studios before being acquired by Valve Software to also work on the game together. It is set in 2008 after a viral pandemic which turns people into mutated, violent creatures hellbent on attacking uninfected humans.
The gameplay focuses on cooperating with your teammates to get to safety at the end of each map. There is also a team-based Versus Mode where up to 8 players compete against each other in teams of 4, Survivors and Infected, to see who can get the most points to win.
