League of Legends (abbreviated LoL or just League) is a multiplayer online battle arena video game developed and published by Riot Games for Microsoft Windows and OS X. The game follows a freemium model and is supported by microtransactions, and was inspired by the Warcraft III: The Frozen Throne mod, Defense of the Ancients. In League of Legends, players assume the role of an unseen "summoner" that controls a "champion" with unique abilities and battle against a team of other players or computer-controlled champions.