Months before Call of Duty: Modern Warfare even hit store shelves, rumors were swirling that the game would feature a battle royale mode. Despite this, Activision remained tight-lipped about any kind of battle royale for Modern Warfare, not officially confirming its existence until a day before it was launched. The recently released Call of Duty: Warzone was one of the worst-kept secrets in gaming, but it's turned out to be one of the year's best surprises.