Grendel is depicted as an evil mindless monster whose only goal is destruction and spreading evil. Considering that he's not depicted as an intellectual tactician but rather as a brute who wants to eat others, he would probably just heal up and attack again. Either that or he would ask for help from his mother.
When you use imagery in poetry it helps you to visualize it more or better.
Visual effect of poetry.
You should be able to find it in the Table of Content, which is in the very beginning of the book.
