Music and joy occurring loudly in the hall irritates Grendel and becomes his motive for attacking Herot. Grendel terrorizes Herot because he is envious of the people's happiness. His jealousy consumes him, and he decides to attack Herot.
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Beowulf is the longest epic poem in Old English, the language spoken in Anglo-Saxon England before the Norman Conquest. More than 3,000 lines long, Beowulf relates the exploits of its eponymous hero, and his successive battles with a monster named Grendel, with Grendel’s revengeful mother, and with a dragon which was guarding a hoard of treasure.
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