It wasn’t because he threw that battle-ax that i turned on hrothgar. that was mere midnight foolishness. i dismissed it, thought of it afterward only as you remember a tree that fell on you or an adder you stepped on by accident, except of course that hrothgar was more to be feared than a tree or snake. it wasn’t until later, when i was full-grown and hrothgar was an old, old man, that i settled my soul on destroying him—slowly and cruelly.

what does the author use in this excerpt to develop grendel’s character?