Following the recent launch of Final Fantasy XIV in China, publisher Shanda Games quickly converted Aion: The Tower of Eternity to a free-to-play model on 29th August 2014. Shanda Games claimed the move is to lower the entry barrier and encourage more new users to try out the game.
It seems the free-to-play model will be based on the cash shop, while no content is being blocked from the free users. The new content patch introduced the 1600-man cross server PvP mode, along with several new open world bosses. Developer NCsoft is currently preparing version 5.0 as well.