Based on the works of Michael Moorcock, Hawkmoon is a stand alone role playing game that can also act as a supplement for the Stormbringer RPG. The box set contains the following: - The Players Book: background information, timeline, character creation, weapons, skills and more. - Science Book: information on technology, invention, travel between the planes and more. - Gamesmaster Book: creatures, mutants, treasure, a starting adventure and more. - Reference Sheets: various tables and assorted information gathered from the books. - Map of Europe: as it exists in the setting - 3 dice: d6, d8, d20. Hawkmoon is compatible with versions 1 to 4 of the Stormbringer RPG. In 2007, Mongoose Publishing announced their acquisition of publishing rights for RPGs based on Michael Moorcock's works. Shortly thereafter they released an RPG in this setting, also calling it Hawkmoon.