Challenger

This book is the seventh installment in a continuous narrative arc and relies heavily on established character relationships and plot developments from the preceding six volumes. New readers should begin with the first book, Forge Master, to understand the protagonist's history and the mechanics of the world.

The Tower series shares the same world as the author's Titan series, and both feature the protagonist Thorn. While they exist within a shared universe, the Tower series follows a distinct progression that builds upon events occurring after the conclusion of the primary Titan narrative.