Eybl was the eldest son of Adam and Iyv. He took a disliking to Kayn, when he came to live in Iyden. Eventually this antagonism lead Kayn to murder Eybl out of rage. Adam attempted to avenge the death of his son during Lilith’s invasion of Iyden, yet failed.
Eybl, the first human to die and be resurrected, was reborn as the final son of Adam and Iyv, and future tyrant of Avalon, Seth.