This book innovatively combines traditional manuscript study with contemporary cultural game theory to show how the enigmatic fourteenth-century Middle English romance, Sir Gawain and the Green Knight, launches a multidimensional game with the reader in its unique manuscript context, Cotton Nero A.x. The authors argue that the poem positions the reader as a player who constructs meaning through the poem's multivalent games within games: the exchange-of-winnings game nested within the exchange-of-blows game, nested within the Christmas games of Arthur's court. The reader's agency especially comes to the foreground when one takes the gaming aspects of the manuscript layout into account. The varying placement of the bobs, along with other codicological aspects of MS Cotton Nero A.x, brings a meta-textual level of game into play, one that ultimately authorizes reading as a variable action. The authors conclude that fluid reading does not undermine the spiritual devotion evoked in the manuscript, but deepens it through the dialectic of game.