Book 2 of the Second Chronicles of Thomas Covenant
Knowing that the fabled One Tree may hold the only means of breaking Lord Foul's power, Thomas Covenant and Linden Avery embark on a perilous voyage to discover its location. On their journey, Covenant and Avery will explore new realms and meet new peoples.
Even far from the Land, however, the grip of evil is strong and there are many who would see them fail. Soon, Covenant and Avery's quest becomes a desperate fight for survival.
Stephen Donaldson