Mythic Britain is a complete sourcebook for adventuring in Britain's Dark Ages using the RuneQuest rules. The book includes an extensive history and background of 5th and 6th Century Britain; details of the different tribes and territories; complete character creation rules for Britons and Saxons, details of magic, the Saints and pagan Gods; and, rules for massed battles. Completing the book, seven linked scenarios form the Mythic Britain Campaign in which the characters travel the length of breadth of the island, serving Merlin and Arthur, fighting the Saxon invaders, searching for the lost Treasures of Britain, and becoming involved in all manner of schemes and intrigues.