An Ice Warrior crashed to Earth during the medieval times and found out that his spaceship was damaged from the impact. He soon made his way into the court of King Halfur and demanded that he be given materials and workers to repair his ship. When King Halfur refused and sentenced him to death, the warrior allowed the king's knights to attack him.
The only knight who was brave enough to attack the Ice Warrior was Sirgwain whose sword proved ineffective against the warrior's armor. After this, King Halfur agreed to let the warrior acquire the materials and workers needed to repair his spaceship. Before leaving, the warrior told Sirgwain to meet him in one month.
One month later, Sirgwain met the warrior outside his spaceship with as agreed. The warrior took Sirgwain's sword away from him and used it to cut down a tree. He then approached Sirgwain and tapped it against his breatplate, stating that honor is satisfied.
The warrior then told Sirgwain to take the workers back to King Halfur and entered his repaired spaceship which then took off and flew into space. (PROSE: Sirgwain and the Green Knight)