Dota 2 is a 2013 multiplayer online battle arena video game and the stand-alone sequel to the Defense of the Ancients (DotA) Warcraft III: Reign of Chaos and Warcraft III: The Frozen Throne mod. Developed by Valve Corporation, Dota 2 was released as a free-to-play title for Microsoft Windows, concluding a public beta testing phase that began in 2011. OS X and Linux versions of Dota 2 were released on July 18, 2013. The game is available exclusively through Valve's content-delivery platform, Steam.
Dota 2 is played in discrete matches involving two five-player teams, each of which occupies a stronghold at a corner of the map. Each stronghold contains a building called the "Ancient", which the opposite team must destroy to win the match. Each player controls a "Hero" character and focuses on leveling up, collecting gold, acquiring items and fighting against the other team to achieve victory.
Development of Dota 2 began in 2009, when the developer of the DotA mod, IceFrog, was hired by Valve as lead designer. Dota 2 was praised by video game critics, who lauded its rewarding gameplay, enhanced production quality and faithfulness to its predecessor. However, the game was criticized for its steep learning curve and inhospitable community. Dota 2 has become the most actively played game on Steam, with daily peaks of over 800,000 concurrent players.[5]