When a chance came, he caught the hero in a rush of flame and clamped sharp fangs into his neck. Beowulf's body ran wet with his life-blood: it came welling out. (2690-2693)
The poet doesn't spare us a final scene of violence: Beowulf's death, seemingly from a severed artery in his neck. Even our hero becomes no more than a corpse by the end of the epic. Now that's depressing.