Grendel fleeing into the darkness with his fatal wound is part of the rising action in Beowulf. Freytag's pyramid consists of exposition, rising action, climax, falling action and resolution. The rising action takes a big part of this story, including the confrontation between Beowulf and the monster Grendel and Grendel's subsequent death, and it leads to the climax, in which Beowulf kills Grendel's mother.
