Publisher Focus Home Interactive and developer Saber Interactive have announced World War Z has sold over one million copies

The new milestone was reached within the first week of the game being available.

“We are humbled and thrilled by the immense success so far of World War Z, especially on PC thanks to the tremendous support of the Epic Games Store,” said Saber Interactive CEO Matthew Karch in a press release. “Moving forward, we’ll continue to expand the game and its community with new improvements, stability updates, and bonus gameplay content, beginning very soon with a special new mission for the Tokyo episode.”

Here is a brief rundown on the game:

Powered by Saber’s dynamic Swarm Engine, World War Z unleashes hundreds of fast-moving, bloodthirsty zombies—able to move and strike as one collective herd as well as break off into individual attackers—at a time on players. Choose from six distinct classes and an arsenal of deadly weapons, explosives, turrets and traps. Outlive the dead through intense four-player co-op campaign missions around the world, including New York, Jerusalem, Moscow and Tokyo, and battle both zombies and real human opponents in competitive, team-based Players vs. Players vs. Zombies (PvPvZ) multiplayer.

World War Z is currently available for Windows PC, PlayStation 4, Xbox One.