State of Decay’s second expansion, Lifeline, will launch on Steam and Xbox Live Arcade May 30 for $6.99, developer Undead Labs announced today.

“If all goes well,t his may be the first time in gaming history that a game was released BEFORE the official public target,” reads a post on the studio’s official website. “It’s a long story, best told over copious quantities of frosty beverages, but the short version is that both the Undead Labs team and the crew at Microsoft has been burning the midnight oil to make this happen before State of Decay celebrates its first birthday.”

As shown in the trailer above, Lifeline adds a new city, a new story (centered around a group of soldiers going on one last mission), and new strategic options to the cult-hit zombie-survival open-world game.

State of Decay debuted on Xbox Live Arcade last year, on June 5, followed by a Steam Early Access release for Windows PC on September 20 and a full launch on Windows PC November 5. Its first expansion, Breakdown, launched on both platforms November 29.

Source: Undead Labs