There is certainly a rhythm to Grendel's warlike appearance here. He is personified as the devil or devil-like. The author uses alliteration to add impact to a galloping like pace in which Grendel advances (ex. bogs- bearing / trap-trip / God -Grendel).
The rhythm of the lines reflect the relentless,ominous approach of Grendel as he advances on Heorot,"Grendel came, hoping to kill""eg God-Grendel.The author uses alliteration to add impact to a galloping like pace by which Grendel advances.Grendel has been personified like a devil or devil like.
