Tempus Fury (Time Shards Series #3)

They call it “the Event”—an unimaginable cataclysm that renders 600 million years of the world's timeline into jumbled fragments. Our Earth is gone, instantly replaced by a new one made of fractured remnants of the past, present, and future. All exist alongside one another in a nightmare patchwork of “time shards”—some hundreds of miles long, and others no more than a few feet across. With surprising help from throughout history, an American girl and her companions first must save ancient Alexandria, the last bastion of civilization, from a panzer tank invasion. Then they will face the ultimate challenge at the end of the world… the shatterfield. Crossing it sends them on a final quest spanning time, space, and dimensions. Only then will they learn if their mission will save their world—or destroy it.