Call of Duty: Warzone was launched within 24 hours of its announcement, and while one might think this lack of advertisement would be detrimental, the game has had no problem establishing a massive following. It's been announced that Call of Duty: Warzone has now passed 15 million players worldwide, proving definitively that the battle royale craze is far from over.

Call of Duty: Warzone passed 6 million players within 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 to Warzone online 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 praised Call 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 system has 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 why Warzone has proven to be such a big hit.

Of course, there are other factors that have played a role in Warzone's success as well. Arguably the biggest is the fact that Warzone is free-to-play. It's true that Warzone can be accessed through the Modern Warfare menus, but for all intents and purposes, it is a standalone product, available as a free download regardless of if one actually owns MW or not. This has greatly expanded its potential player base, and will likely ensure that the Warzone player 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 if Warzone will 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 what Infinity Ward releases for Warzone in the weeks and months to come to keep fans engaged.

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

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