As Ray Bradbury said, the Oz books are for everyone, adults and children alike. Some people have never gotten beyond Dorothy and the Wizard or only saw the movie, but other Oz books are even more eccentrically original.

Ruggedo the Nome King (later changed to Gnome King by Ruth Plumly Thompson, who continued the series) appears in several books in the series (see the list below). His original name was Roquat, also known as the Metal Monarch.  Remarkably, eggs are poison to Nomes. As Ruggedo put it, “Hens are bothersome at their best, but when they can talk they’re simply dreadful.”

Ruggedo incessantly seeks to wreak havoc on the Emerald City of Oz and its inhabitants. The problem usually is resolved by having him drink from the Fountain of Oblivion (which never seems to have a lasting effect on him, so he’ll be back).

In his first appearance in Ozma of Oz the nome king transforms the royal family of Ev into bric-a-brac to decorate the rooms of the palace. Ozma, Dorothy, and others come to the rescue.

In The Emerald City of Oz the nome king tries to take revenge by digging a tunnel under the Deadly Desert and recruiting evil spirits.

In Tik-Tok of Oz Ruggedo fights against a dragon.

In The Gnome King of Oz, Ruggedo. aided by the boy Peter (carried off from Philadelphia by a balloon bird), tries to regain his magic belt from Ozma. The book includes quirky elements like the footbridge that literally “runs” to the Emerald City (on legs), the usual intriguing magic, and evocative scenes such as the sea quake, which causes the sea to turn upside down, revealing a pirate ship.

The Magic of Oz is my favorite, featuring not only the irascible Ruggedo himself but the equally bad-tempered boy Kiku Aru (“I have always wanted to be wicked, but I didn’t know how”) and a cast of unforgettable characters, such as the Glass Cat, who is vain about her pink brains  (you can see them working), emerald eyes, and ruby heart, which is visible through her transparent body. In an entertaining story line Trot and Cap’n Bill set out to obtain the Magic Flower  (which keeps changing blooms)  as a birthday present for Ozma and get stuck on the magic island  (they grow roots) in scenes that I’ve remembered since childhood.

Meanwhile Kiki Aru transforms himself and Ruggedo into eagles with a secret magic word (Pyrzqxgl: all my attempts to pronounce  it so far have failed, but perhaps you’ll have more success). They fly to the forest to persuade the beasts to overthrow Oz: they’ll become people and the people will become animals.

All the Oz books suffer from being episodic and at times excessively cute. (After all, they were written 100 years ago.) But they are wonderfully inventive, full of original and quirky characters  and memorable scenes.

http://oz.wikia.com/wiki/Ruggedo (includes a series history of Ruggedo)

http://newwwoz.blogspot.com/2013/09/the-characters-of-oz-roquatruggedo.html

Ruggedo sites:

The Magic of Oz (1919)/The Gnome King of Oz (1927):  Ruggedo

By L. Frank Baum:                                 

Ozma of Oz                                         
The Emerald City of Oz                          
Tik-Tok of Oz

The Magic of Oz                                  

The Little Wizard Stories of Oz               

Oz books that feature Ruggedo:

By Ruth Plumly Thompson:

Kabumpo in Oz
The Gnome King of Oz
Pirates of Oz
Handy Mandy in Oz

The Hungry Tiger of Oz