Fortnite: Save the World is a cooperative hybrid-third-person shooter tower defense survival video game developed and published by Epic Games. The game was released as a paid-for early access title for Microsoft Windows, macOS, PlayStation 4 and Xbox One on July 25, 2017, with plans for a full free-to-play release announced in late 2018. Epic eventually opted to move the game to pay-to-play in June 2020. The retail versions of the game were published by Gearbox Software, while online distribution of the PC versions is handled by Epic's launcher. Fortnite is set on contemporary Earth, where the sudden appearance of a worldwide storm causes 98% of the world's population to disappear, and zombie-like creatures rise to attack the remainder. Considered by Epic as a cross between Minecraft and Left 4 Dead, Fortnite has up to four players cooperating on various missions on different maps to collect resources, build fortifications around defensive objectives that are meant to help fight the storm and protect survivors, and construct weapons and traps to engage in combat with waves of these creatures that attempt to destroy the objectives. Players gain rewards through these missions to improve their hero characters, support teams, and arsenal of weapon and trap schematics to be able to take on more difficult missions. The game is supported through microtransactions to purchase in-game loot boxes that can be used towards these upgrades. A standalone battle royale game version, Fortnite Battle Royale, was released for the same platforms in September 2017. Following the release, the player-versus-environment mode was officially distinguished as "Save the World".