Isbrand is the ancient vampire who turned Brencis. A strict keeper of the old vrakhiri laws, he wanted their kind kept hidden, and Lacra believes he knows how to hurt Brencis.
Isbrand was far older than Brencis and a traditionalist. He fed on humans without remorse but kept to principles: he exiled Lacra for her part in Brencis's research rather than kill her.
Lacra wants to question him about Brencis's weaknesses. The Uriash Matriarch reveals where he is in Song of the Mountain, and Hive and Seek takes you through a kobold cave to reach him.
Brencis, Ambrus and Bakir could not beat him until Xanthe's blood whips held his limbs. They buried him alive in a cave, where kobolds fed on him for years, since his healing made him an endless food source.
He sired Brencis and travelled with him and Lacra. He forced Brencis to watch his wife Helvia die to cut his ties to the past, and later told him he should have killed him.