Flames Of Mira - Book One of The Rift Walker Series

Set in a world of ice and fire, where people live underground and your proximity to heat suggests your status, Ig is a slave. Gifted with amazing abilities to manipulate metals, he is enslaved to the local ruler by a powerful enchantment that has turned him into an unwilling executioner. When revolution comes to the city, Ig must fight not just for this freedom, but for his very identity.