She drags him down to her underwater lair.
After engaging Grendel's mother in battle, Beowulf is saved by his chainmail armor when she tries to stab him with a dagger. He then sees a magical sword, named Hrunting, hanging on the wall and uses it to defeat Grendel's mother by decapitating her.
After engaging Grendel's mother in battle, Beowulf successfully decapitates her with a magical sword he finds in her lair, thus avenging the death of Hrothgar's advisor, Aeschere. Beowulf emerges victorious and returns to Heorot with Grendel's head and the hilt of the sword as proof of his triumph.
While Grendel's mother is hard for Beowulf to defeat, he IS able to use a sword, where as he has to battle Grendel bare handed.
In the first battle of Beowulf, Grendel is mortally wounded by Beowulf when he forcefully rips off the monster's arm. Grendel retreats to his swamp lair and dies from his injuries.
In chapter 8 of Beowulf, Beowulf prepares to face the dragon that has been terrorizing the Geats. Despite his advanced age, Beowulf remains determined to defend his people and emerges victorious after a fierce battle. However, he is mortally wounded in the process and dies shortly after defeating the dragon, bringing an end to his legendary life.
Both Beowulf and Grendel are portrayed as powerful and formidable foes. They both possess extraordinary strength and prowess in battle. Additionally, both characters are depicted as central figures in the epic poem "Beowulf" and play crucial roles in the narrative.
Hrothgar asks Beowulf to battle Grendel's mother because she is seeking revenge for Grendel's death, posing a new threat to the kingdom. Beowulf's bravery and skill in defeating Grendel make him the best candidate for facing this new challenge.
Beowulf's sword is useless against Grendel's mother because her skin is too tough for it to penetrate. The sword shatters upon impact, leaving Beowulf vulnerable in the battle. Ultimately, it is Beowulf's strength and willpower that allow him to defeat Grendel's mother.
In section XIX of Beowulf, Beowulf swims in the sea to reach the underwater lair of Grendel's mother. He engages in a fierce battle with her, ultimately killing her by beheading her with a sword he finds in her lair. Beowulf then presents the head of Grendel's mother to Hrothgar as a trophy of his victory.
Beowulf's throne is abandoned when the dragon starts rampaging. Only Wiglaf remains by Beowulf's side to help him in the battle against the dragon.
Grendel's mother mourns the death of her son by seeking revenge on Beowulf, who killed him. She attacks Heorot in search of retaliation, ultimately resulting in a battle with Beowulf himself.
He is attacked by Beowulf and Beowulf tears his arm off and injures him very badly. Grendel then escapes, but is so badly wounded that he dies, and Beowulf is seen as a hero. Later, Grendels mother goes to avenge Grendel's death.
Underwater, in a lake.