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Drew knows there are two rules to using the time portals. One, be precise in thought. Two, never visit the future.
On his second practice run, a stray thought of wanting to see life 1000 years in the future lands him, along with Oz, the Emperor, Aisha, and Wick in 3416. San Francisco is in ruins. The Embarcadero is gone, the Bay Bridge is a broken skeleton, and the city has been overtaken by a dark wizard named Tobias. The only one who can destroy his power and his hold over the elfin citizens of Saint Francis is a clumsy, sword-wielding fifteen-year-old boy, the wizard Hagar and his fading magic, and the Trident--warriors of time long past who will stand beside the Lord of Prophecy.
Hagar knows their names and declares them as the Trident, prompting Will to agree to indulge Oz and Drew's curiosity and stay long enough to understand the truth of how Hagar knows who they are. He could not foresee the horse-sized cat named Fluffy, the infant dragon named Jeff, or the truth about Tobias.
As he puts the pieces of the puzzle together, Will realizes the fight isn't just to free the elves; it's a battle Oz needs to see to the bitter end, and he'll risk them all to get her there.