Call of Duty: Warzonepassed 6 million playerswithin its first day of availability, so it’s not surprising to see that it’s already passed 15 million players. It’s still an impressive feat, though, and a testament to the game’s quality. The general reaction toWarzoneonline has been largely positive, with much praise given to the various innovations that it has introduced to the battle royale genre.

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For example, fans have praisedCall of Duty: Warzone’s loot system, as it requires much less micromanagement as other games in the genre.Call of Duty: Warzone’s 1v1 Gulag respawn systemhas also been well-received, as it utilizes the popular Gunfight mechanics and gives players a fun way to earn their way back into a match if they happen to die early on. These features have been hugely popular and can be given at least partial credit for whyWarzonehas proven to be such a big hit.

Of course, there are other factors that have played a role inWarzone’s success as well. Arguably the biggest is the fact thatWarzoneis free-to-play. It’s true thatWarzonecan be accessed through theModern Warfaremenus, but for all intents and purposes, it is a standalone product, available as a free download regardless of if one actually ownsMWor not. This has greatly expanded its potential player base, and will likely ensure that theWarzoneplayer count continues to grow for some time.

Other battle royale games have had no problem creating large player bases at the start, but many have struggled to maintain those numbers on a long-term basis. It remains to be seen ifWarzonewill buck that trend, but it seems like it has a decent shot at staying popular for some time to come. It will be interesting to see whatInfinity Wardreleases forWarzonein the weeks and months to come to keep fans engaged.

Call of Duty: Warzoneis out now for PC, PS4, and Xbox One.