Warcraft III: The Frozen Throne is an expansion pack of Warcraft III: Reign of Chaos developed for Microsoft Windows, Mac OS and Mac OS X by Blizzard Entertainment. Released in stores worldwide in multiple languages beginning on July 1, 2003,[1] it details Arthas' transformation into the Lich King, Illidan's awakening of the naga, the conversion of the blood elves, the breakdown of Horde-Alliance relations in Kalimdor, and more. The Frozen Throne takes place approximately one year after Warcraft III: Reign of Chaos, whilst World of Warcraft takes place three years after the events detailed in The Frozen Throne.