Entropia Universe is a social MMORPG developed by MindArk with the distinction of having a real cash economy. Players can invest money into the game for paid upgrades, trades, and investments, and can also convert earned in-game currency into real life money and withdraw their profits. The game itself, a sci-fi virtual world, casts players as colonists in a multi-planet environment filled with resources, as well as deadly creatures. Many planets are available to discover, such as the sci-fi planet of Calypso and the Hollywood-inspired music world of Rocktropia. The basic game is free to download and play, but is limited.