The Targothian: The Circle Closes - Targothian Trilogy, #3

With the world safe and the Crimson Death a distant memory, Sargas settles down to live out the rest of his life, now fully mortal and aging normally again. However, in his sunset years and now an elderly man, he is requested to come to meet someone claiming to be the son of his old enemy, Gostal. Facing this new threat, the original Targothian Knight regains his powers and sets himself upon a course that will take him to a faraway planet, a strange dimension, and ultimately meet a destiny which has been a very long time in the making.