Planetarion is a browser-based massively multiplayer online game created by Fifth Season AS in early 2000. The game places players in control of a planet, with the ability to mine its asteroids for resources, enabling them to construct a fleet of spaceships to attack other players' planets. Although its popularity has declined with the emergence of other similar games and the introduction of a pay-to-play model, which has since been changed to a freemium format, the game is currently still active, and as such is one of the oldest running internet games of its genre.