Thorbiorn now turned to Illugi, and said, "It is a pity that a brave lad like you should die, because you are associated with outlaws and evil-doers."
"I tell you this," said Illugi, "that I will appear before you at the great assize, and there will charge you with having practised witchcraft to effect my brother's death."
"You hearken to me, boy," said Thorbiorn. "Put your hand to mine, and swear that you will not seek to avenge the death of your brother, and I will let you go; but if you will not take this oath, you shall die."
"And hearken to me, Thorbiorn," said lllugi. "If I live, but one thought shall occupy my heart night and day, and that will be how I may best avenge my brother. Now that you know what to expect of me—take what course you will."
Thorbiorn drew his companions aside to ask their advice; but they shrugged their shoulders, and replied that, as he had planned the expedition, he must carry it out as he thought best.
"Well," said The Hook, "I have no fancy for having the young viper lying in wait to sting me wherever I tread. He shall die."
Now, when Illugi knew that they had determined on slaying him, he smiled and said, "You have chosen that course which is best to my mind. I do not desire to be parted from my brother."
The day was breaking. They led Illugi to the east side of the island, and there they slew him.
It is told that they neither bound his eyes nor his hands, and that he looked fearlessly at them when they smote him, and neither changed colour nor even blinked.
Then they buried the brothers beneath a cairn in the island, but they took the head of Grettir and bore it to land. On the way they also slew the thrall Glaum.