PUBG, created by Brendan 'PlayerUnknown' Greene, did not invent the battle royale concept, but it made it mainstream. One hundred players parachute onto an island, scavenge for weapons and equipment, and fight inside a shrinking safe zone until one player or squad remains. Greene had been iterating on the idea through ARMA 2 and ARMA 3 mods before partnering with Bluehole Studios (later PUBG Corp) to build a standalone game. It sold over a million copies in early access within weeks, hit 3 million concurrent players on Steam, and triggered the battle royale gold rush that brought us Fortnite, Apex Legends, and Warzone.