Released in 2013, Cataclysm: Dark Days Ahead (CDDA) is an open-source community-developed survival horror. Players are given complete freedom in a modern world ravaged by every apocalypse imaginable, from triffids and zombies to interdimensional monstrosities. Explore the world, take the fight to the fiends, or cower in a bunker; the choice is in the players' hands. Survival is the only goal, and death is the sole certainty.