Diablo is an action role-playing hack and slash dungeon crawler video game series developed by Blizzard Entertainment. , the series has sold over 24.8 million copies worldwide. The series is made up of three core games: Diablo, Diablo II, and Diablo III. All three games are action role-playing and hack and slash games. Expansion games include the third-party published , which follows the first game, Lord of Destruction, published by Blizzard and released after the second game, and the recently released Reaper of Souls, which follows the third game. Additional content is provided through story elements explored in other media forms.