There’s no way around out, PlayerUnknown’s Battlegrounds (a.k.a PUBG) is a phenomenon. Despite generating very little hype prior to release, and being developed by a South Korean studio with a modest budget, the title has generated monstrous popularity. During the past three months we’ve seen popular Counter-Strike: Global Offensive and World of Warcraft streamers shift a large portion if not all their focus onto the title as millions of PC gamers worldwide have devoted hundreds if not thousands of hours to playing the game.

For those who have been watching the open-world survival genre, this doesn’t come as too much of a surprise. Titles ranging from ARMA 2‘s DayZ mod to H1Z1 have generated similar interest despite being very unpolished games. Equipped with the Unreal Engine and a new angle on survival, PUBG‘s has ushered a new era for the genre that has become one of 2017’s most notable titles.

Just three months after release, PUBG‘s creative director has confirmed the milestone with the following tweet:

3 months… 4 million copies of @PUBATTLEGROUNDS sold… Thank you all again for your continuing support <3

This makes PUBG the best-selling game of 2017 so far, all this despite being PC exclusive, and technically not even out yet—it’s still in early access.

PUBG‘s greatest sales rivals include The Legend of Zelda: Breath of the Wild at around 3 million units sold, Horizon Zero Dawn at 3.4 million units sold, and Resident Evil 7 at 3.5 million units sold.

Microsoft announced at E3 that it has partnered with Bluehole to bring PUBG to Xbox One as a timed exclusive. This partnership will, at the very least, last through this holiday season, at which point the title may be ported over to the PS4.