Call of Cthulhu (1981)

The first printing of Call of Cthulhu contains a 96-page Call of Cthulhu book, a 32-page Sourcebook for the 1920s, an updated edition of rules of the Basic Role-Playing system, a fold-out world map, a book of character sheets, cardstock figures to be cut out, and some dice.

The Call of Cthulhu book includes information on the background setting, character creation, available skills, character sanity control, Cthulhu creatures and mythos, magic, scenarios, and area maps.

"A Sourcebook for the 1920's" includes information on timelines, biographies, companies, crime, railway coaches, travel, price charts, weapons, and beasts and monsters.

The game uses a simplified version of Chaosium's Basic Role-Playing system.