This book innovatively combines traditional manuscript study with contemporary cultural game theory to show how the fourteenth-century Middle English romance Sir Gawain and the Green Knight launches a multidimensional game with its late-fourteenth-century elite reader in its unique manuscript context, London, British Library, Cotton MS Nero A X/2. The textual and visual games of Sir Gawain and the Green Knight and the Cotton Nero manuscript allow a fourteenth-century English Christian aristocracy to align courtly gaming with heavenly goals, thereby justifying elite amusements.