The Green Knight is not named in the poem, and he says only that men know him as the "Knight of the Green Chapel." His strange color and his marvelous ability to live without his head mark him as an otherworldly creature. In other ways, however, he could simply be an especially bold knight. He is enormously tall and strong, almost a giant, and his vigor and maturity are indicated by his bushy hair and beard. He is brash and rude in his challenge to the court, calling them mere children and telling them that if he had come to fight, no one could stand against him. He says he comes to the court in peace, asking only for a game, and yet he carries a fearsome weapon, a huge axe.
When Gawain meets the knight again at the Green Chapel, he is again fearsome, but also playful, tweaking Gawain by drawing out the final blow, alternately mocking him for cowardice and praising him for bravery. When it finally becomes clear that he does not intend to kill Gawain, the Green Knight seems more mischievous than frightening. He has indeed been playing a game with Gawain, but a different game than the one Gawain imagined.
The pattern of the romance leads to the expectation that the Green Knight is a villain, an evil monster. However, when the story ends, Gawain and the Green Knight part as friends. Far from having been defeated, the Green Knight retains the advantage throughout the story, and the poet leaves him to go his ways, his mysteries unexplained and his ambiguities unresolved.