Undead Labs' breakout XBLA hit State Of Decay has now sold 500,000 copies.
State Of Decay became the fastest-selling original XBLA game when it reached 250,000 sales after just two days. By doubling that amount little more than a week later, Undead Labs has proved its game is no flash in the pan.
"State Of Decay breaks a lot of rules. Permadeath, switching characters, having to manage the "feelings" of your fellow survivors, offline progression - these are all things developers traditionally avoid, but we felt were essential to creating a true survival experience," said Undead Labs founder Jeff Strain in an interview for the Xbox blog.
"Record breaking sales are great, but the thing we're proudest of is that people who bought the game are having a great time playing it. That's why we do what we do, and what keeps us going back in to do it again."
Undead Labs is currently working on a PC version of State Of Decay and, according to a report on Eurogamer, its future plans include an MMO set in the game's universe, tentatively titled "Class4." However, that project is still waiting for approval from Microsoft.
"We cannot begin working on Class4 without a greenlight from Microsoft - who owns the IP, as part of the bargain that led to the funding and development of State of Decay - and a mutually agreeable contract," said Sanya Weathers, Undead Labs' director of community.
"We have to agree on where we think the technology is going to be in a few years, since the game will take a few years to develop. We have to agree that we have the same goals, and we have to agree on how we'll collectively run and support the final game."