Grendel was a "powerful monster, [who was] living down in the darkness" (Raffel 1-2).
Grendel was really curious so he " [w]ent up to Herot, wondering what the warriors/ Would do in that hall when their drinking was done" (31-32).
Grendel snatched up 30 men at the Hall, then before you know it "Grendel came again, so set/ [o]n murder, that no crime could be enough" ( 50-51).
Grendel did not change at all he was still " Killing as often as he could,coming/ [a]lone, blood thirsty and horrible" (80-81).
Beowulf comes in the picture now and now he is " [p]roclaiming that he'd go to that famous king, / [w]ould sail across the sea to Hrothgar" (114-115)
Grendel and Beowulf decided to fight each other. During the battle Grendel was losing so bad and " he twisted in pain,/ [a]nd the bleeding sinews deep in his shoulder/ [snapped] muscle and bone split/ [a]nd broke. The battle was over" (389-392)