Grendel's Mother and the Hydra of Hercules

As Seamus Heaney says in the introduction of Beowulf, Grendel and his mother are “figures who do the devil’s work...who call up and show off Beowulf’s physical might and his superb gifts as a warrior.  They are the right enemies for a young glory-hunter.” Thus, Grendel's mother is an obstacle, for Beowulf to overcome and show off his strength and his natural talent for battle. An example of this in other stories is the hydra from one of Hercules' adventures. The hydra, also known as the Lernean hydra, had nine heads, and of the nine, eight were mortal and the ninth was immortal. The hydra was an obstacle that brought out the quick thinking and immense strength of Hercules. Like Beowulf, Hercules was gifted with superhuman strength, and Hercules used this to his advantage as he grappled with the hydra, armed with nothing but a club and his bare hands. While Grendel and his mother are examples of monsters, or obstacles, that are placed in the hero's way to display the hero's traits and talents, the Lernean hydra serves this purpose in Hercules' adventures to show his quick thinking and how he uses his strength in handling the monster. Grendel's mother presents a tough battle that Beowulf "barely survived the battle under water" (page 115 line 1655), and only by using his God-given gift of strength as well as some quick observations, Beowulf just managed to use the giant blade to slay Grendel's mother. Hercules, on the other hand, confronts the venom-spitting Lernean hydra by smashing the mortal heads in with his club. However, for every head that was destroyed, two more would grow in their place. Hercules and his nephew Iolaus, used some quick thinking and burned the stumps of the heads to prevent the heads from growing back. Eventually, Hercules cut off the immortal head and buried it on the side of a road with an enormous rock on top of it, to prevent it from growing back into another hydra. Without Hercules' inhuman strength, he would not have been able to hold the hydra's heads still to smash them, or even put the heavy rock on top of the immortal head to prevent it from growing again. Thus, Grendel's mother and the Lernean hydra are similar monsters that display the respective hero's traits and talents as a warrior.

Just as an aside, while Grendel's mother and the hydra are similar, Beowulf and Hercules are quite similar heroes as well. While Beowulf does receive some "magical boons" to fight Grendel and his mother, the weapons become useless under the supreme protection of Grendel's skin. With the exception of the giant's blade and Beowulf's chainmail shirt, there weren't really any other boons given to Beowulf to defeat Grendel and his mother. Hercules also did not receive any magical instruments to defeat the hydra, relying only on his nephew, his strength and his quick thinking.