Dota 2

Dota 2 is a 2013 multiplayer online battle arena video game and the stand-alone sequel to the Defense of the Ancients  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.

Download it from here:
http://store.steampowered.com/app/570/