The world of a zombie apocalypse is one full of horror and despair. The once-lively streets are deserted and filled with rotting bodies. The world is full of danger and evil, where a single mistake can cost you your life. The sound of gunfire and explosions rings out through the air, and the sight of blood and gore is a common sight across the landscape. After the zombies appeared, some people mutated. They could develop animal features and superpowers.