Weak, typically anything that is cited from wikipedia is seen as unreliable
The used rhetorical device is Hyperbole.
Saying that something is a billion times better is hyperbole because it is not really that much better, you would just be over exaggerating.
answer i would have to guess that C. Unferth challenges Beowulf again, and the two fight to the death. There is no way that Beowulf would ever give up a good fight for any reason, especially for a maiden. Grendel could not defeat Beowulf for Beowulf must still fight Grendel's mother and the dragon, nor would Grendel venture into the kingdom so openly. The king needs Beowulf to save them from Grendel so he would not double-cross him