"...A fiend out of hell
began to work his evil in the world.
Grendel was the name of this grim demon
haunting the marches, marauding round the heath
and the desolate fens; he had dwelt for a time
in the misery among the banished monsters,
Cain's clan, whom the Creator had outlawed
and condemned as outcasts..." (lines 100-107)
Grendel is the first demon that Beowulf battles with. A descendent of Cain, he slaughters and devours the men of Heorot each night for twelve years, before Beowulf comes from Geatland to defend Hrothgar and his glorious hall.
The monster was gruesome, with talons and teeth, long and sharp. His skin was inpenetrable to steel, so no man could wound him with a sword, but he wasn't strong enough to defend himself against Beowulf--his encounter with the warrior left him an arm short, from the shoulder down. After the battle, he slinked back to the swamp he lived in to die.
"Grendel's mother,
monstrous hell-bride, brooded on her wrongs.
She had been forced down into fearful waters,
the cold depths, after Cain had killed
his father's son, felled his own
brother with a sword..." (lines 1258-1263)
Grendel's mother came back to reak havoc in Heorot after Grendel was killed by Beowulf. (see p. 65 to finish)
"Unferth, the strong-build son of Ecglaf,
could hardly have remembered the ranting speech
he had made in his cups. He was not man enough
to face the turmoil of fighting under water
and risk his life. So there he lost
fame and repute...(lines 1456-1471)