Yellow Brick War (2016)

In this third book in the New York Times bestselling Dorothy Must Die series, new girl from Kansas Amy Gumm is caught between her home—and Oz. My name is Amy Gumm. Tornadoes must have a thing about girls from Kansas, because—just like Dorothy—I got swept away on one too. I landed in Oz, where Good is Wicked, Wicked is Good, and the Wicked Witches clued me in to my true calling: Assassin. The way to stop Dorothy from destroying Oz—and Kansas—is to kill her. And I’m the only one who can do it. But I failed. Others died for my mistakes. Because of me, the portal between the worlds has been opened. And if I don’t find a way to close it? Dorothy will make sure I never get to go home again. Now it’s up to me to: join the Witches, fight for Oz, save Kansas, and stop Dorothy once and for all.