Overwatch is a team-based multiplayer first-person shooter developed and published by Blizzard Entertainment and released on May 24, 2016 for PlayStation 4, Xbox One, and Windows. Described as a "hero shooter", Overwatch assigns players into two teams of six, with each player selecting from a roster of 31 characters, known as "heroes", each with a unique style of play whose roles are divided into three general categories that fit their role. Players on a team work together to secure and defend control points on a map or escort a payload across the map in a limited amount of time. Players gain cosmetic rewards that do not affect gameplay, such as character skins and victory poses, as they play the game. The game was initially launched with casual play, with a competitive ranked mode, various 'arcade' game modes, and a player-customizable server browser subsequently included following its release. Additionally, Blizzard has added new characters, maps, and game modes post-release, all free of charge, with the only additional cost to players being optional loot boxes to earn cosmetic items.