Exile by R.A. Salvatore

The Legend of Drizzt continues with the second installment of The Dark Elf Trilogy where Drizzt has escaped his family, hiding out in the Underdark for the past ten years. Through necessity, he takes on the alter ego of the "Hunter" to cope with the constant dangers of the Underdark, having only Guenhwyvar as his companion in the solitude. However, as time carries on, he starts to lose his humanity, becoming more like the monsters he is forced to fight and desperate to get back into their Goddess' favor, his family begins to hunt for their rogue noble.