Read these lines from beowulf.

he realized
that the demon was going to descend on the hall,
that he had plotted all day, from dawn-light
until darkness gathered again over the world
and stealthy night-shapes came stealing forth
under the cloud-murk.

read this excerpt from grendel.

thus i fled, ridiculous hairy creature torn apart by poetry—crawling, whimpering, streaming tears, across the world like a two-headed beast, like mixed-up lamb and kid at the tail of a baffled, indifferent ewe—and i gnashed my teeth and clutched the sides of my head as if to heal the split, but i couldn’t.

*grendel is described as an unfeeling creature in beowulf, but he is a sensitive and emotional character in grendel.
*grendel seems comical and ridiculous in beowulf, but he seems calm and calculating in grendel.
*beowulf acts cowardly in beowulf, but he behaves like a fearless hero in grendel.
*beowulf feels sympathy for grendel in beowulf, but he is jealous of grendel in grendel.