Leviathan ~The Last Defense~ (絶対防衛レヴィアタン, Zettai Bōei Reviatan, lit. "Absolute Defense Leviathan") is a Japanese mobile game by GREE. The plot features anthropomorphized dragons as characters. It is a freemium game, as the base game is free of charge but game add-ons can be downloaded for various prices. The game was announced in October 2012 and users who preregistered got a rare card. An anime adaptation by Gonzo aired in Japan from April to July 2013.