Aion: The Tower of Eternity, known also as The Tower of AION in Japan, is a massively multiplayer online role-playing game (MMORPG) released by NCsoft, a major Korean game developer. The game combines PvP and PvE (a concept the developers call PvPvE) in a fantasy game environment. As of May 20, 2009, Aion has 3.5 million subscribers in Asia. AION's first major expansion pack was released to North America and Europe on September 7, 2010 under the name AION: Assault on Balaurea. On February 29, 2012 AION became free-to-play on Europe with a limited set of options regarding gathering, trade and chat, while North American Free-to-play launched on April 11, 2012 with no such restrictions.