PUBG Corp. announced today that PlayerUnknown’s Battlegrounds has reached over 4 million players on Xbox One since launching on the system’s Game Preview service on December 12.

PUBG on Xbox One got off to a quick start, selling 1 million copies in three days. That momentum has continued. The original PC version, which left Early Access in December, has sold over 20 million copies. PUBG has attracted imitators, but its success still stands out as one of gaming’s biggest breakouts in recent memory.

The Xbox One release is also getting a new patch later this week. It will include bug fixes and gameplay optimizations.

PUBG Corp. is celebrating the milestone by giving all Xbox One players 30,000 battle points, which they can use to buy cosmetic loot crates. This reward is for any player who has bought or buys the game before the end of the month.