Epic launched the title through a paid early access then, with a full free-to-play release expected in 2018.[56] Following on the popularity of PlayerUnknown's Battlegrounds, a battle royale game released earlier in 2017, Epic developed a variant of Fortnite called Fortnite Battle Royale, which was released in September 2017 as a free-to-play title across computer, console, and mobile platforms. Fortnite Battle Royale quickly gained an audience, amassing over 125 million players by May 2018 with estimates of having earned over US$1 billion by July 2018 through microtransactions, including its battle pass system.