Jack Staples and the Poet's Storm, Book 3 by Mark Batterson & Joel Clark and published by David C Cook.
Our world is more fantastical than we dare imagine ... filled with both unbelievable beauty and horrific evil. Just ask Jack Staples and Alexia Dreager. They’re at the epicenter of the conflict that’s been raging since time before time began. Their birth and destiny have long been prophesied—but things aren’t going as planned.
In this epic conclusion to the Jack Staples trilogy, Jack and Alexia must make an impossible choice during their final battle against the Assassin—one that could alter time itself and the fate of the world.