The Emerald City of Oz
When Dorothy brings Uncle Henry and Aunt Em to the Emerald City of Oz, they begin a tour of the surrounding cities and people, encountering the Cuttenclips, the Fuddles, the inhabitants of Utensia, the Flutterbudgets, and many more. Meanwhile, the Nome King is furious over the loss of his magic belt, and begins gathering an army to dig an underground tunnel to the Emerald City and capture the entire population.
This isn’t my favorite Oz book, but the hilarious wordplays and puns are thicker than ever. Especially in Utensia. I think this one was intended to be the last Oz book, but L. Frank Baum was forced to write more by popular demand.