Borlak is a son of Oberon and is not very happy about it. Once Oberon's boon companion in the conquest of warrior shadows dangerous to a small and growing Kingdom of Amber. There is not argument that he was genetically placed between the four of Oberon's senior children Oscric, Finndo, and Benedict, and a daughter Orsolla, and the Children of Fiella;Eric, Corwin, and Deirdre.
In time Oberon decided he was unsuitable for the company of the people he was bringing to Amber. He exiled Borlak.
Over the millenia Borlak developed