Laiken
Laiken is the is also the most powerful necromancer in Rivellon and according to Lord Lovis, his power is second only to Damian himself. He is also the client to many of the bandits that roam Rivellon, who take whatever loot they find and give their bodyparts to Laiken so that he may use them for his necromantic experiments and thus bolster his undead army.
In order for Laiken to have taken control of the Battle Tower, he needed to undo the spell that Maxos had placed upon it. To do so, he needed the blood of a loved one. That special someone was Sassan, his personal concubine. After sacrificing her and becoming the tower's new master, a part of him began to miss Sassan and regret that which he had done. Being the insane, perverted wizard that he is, he came up with a perfect solution to the problem! He proceeded to gather female bodyparts and create a replica of his beloved Sassan (see Dead Sassan). This "new" Sassan was not nearly as attractive as the old one, but even so she satisfied Laiken's needs.
As Sentinel Island was now under Laiken's rule, the island changed from a wondrous land filled with draconic magic, to a mad circus of death and insanity. In order to achieve immortality, Laiken Soul Forged himself with the immortal demon, Razakel.
The ex-Dragon Slayer chances upon him during The Temple of Doom quest after entering the portal in the Bandit's Cave. At first, he assumes the Dragon Slayer had came to apply as his new corpse delivery person. He quickly panicked when he realizes the new Dragon Knight had come for his Battle Tower. He then shoved the bemused Dragon Knight back to the portal and collapses the ceiling. Such was futile, for he would still meet his end upon the next time meeting the Dragon Knight.
Mindreading
You can mind read him when you meet him for the first time, after defeating Jagon. He will think "Soon I shall unlock the the powers of the Dragon Stone and I will be a Dragon Knight in reality as well as in role". If you use mindreading during the dialog before killing him a chest will appear behind the throne containing his sword and other useful items.
Hall of Echoes
Laiken and Razakel at the Hall of Echoes
Laiken and Razakel are fought again, together this time, at the Hall of Echoes arena.
Divinity II: Flames of Vengeance
In Divinity II: Flames of Vengeance it is revealed in a letter titled Dirty Scrap of Paper that Laiken secretly fathered a child with the bandit known as Cutthroat Carmina.