The End of Oz (Dorothy Must Die #4) by Danielle Paige
Publisher: HarperCollins
Goodreads Summary: 
Ding dong—Dorothy is dead.

I watched as the Emerald Palace crumbled to the ground, burying Dorothy, the Girl Who Rode the Cyclone, under the rubble. And now that the rightful ruler, Ozma, has been restored to the throne…

Oz is finally free.

My name is Amy Gumm. You might remember me as the other girl from Kansas. When a tornado whisked me away to the magical land of Oz, I was given a mission: Dorothy must die.

But it turns out girls from Kansas are harder to kill than we look.

Now the Road of Yellow Brick is leading me away from Oz to the dark world of Ev, where I have a new, powerful enemy to deal with: the Nome King. And—surprise—he has a gingham-clad bride.

With my magical shoes and a shrinking group of allies, I have one final chance to fulfill my mission, and save not only what’s left of Oz, but Kansas, too. As the line between Good and Wicked blurs even further, I have to find a way to get rid of Dorothy once and for all—without turning into a monster myself.

Dorothy once said there’s no place like home. Can I stop her from destroying mine? 
Rating: 4.5 Stars
Amy Gumm is the other girl from Kansas. After leaving Dorothy under a collapsing palace, her next mission is to kill the Nome King. Alongside Nox and former bully Madison Pendleton, the Yellow Brick Road transports them to Ev where they'll need everything they have to restore Oz. Many trials will test them to see if they are truly ready to save Oz.

"'Hi, Amy,' she said. Her grotesque grin had suddenly transformed into a joyful snarl. 'Are you going to kill me now?'"

The theme of books one to three is mainly 'kill Dorothy', while The End of Oz focuses much more on other subjects, such as the downfall of the Nome King, gaining a princess's trust, explaining the magical world to Amy's old tormentor, and why of course, relationship drama. Honestly? I didn't expect that Amy and Nox would be so big a part of the book when previously they'd been minuscule at the most. Sure, I love it, but the element of romance just seems strange when the focus has always been war/violence oriented.

"The air around us held still.
Then the world fell apart."

Sacrifices must be mad if Oz is to be returned to its former glory. This section of the book is bittersweet and conflicting, but all turns out to be okay. This quote really makes you think. All the goals you aspire for, they can become impossible moments after you've achieved them. It makes you wonder if all that hard work was pointless, a constant uphill battle. So why try?

"When she took a last step forward, the magic from our shoes rippled like she was wading through water."

Amy/Dorothy's shoes are a crucial part of the ending, something which makes me wonder why Danielle Paige chose to end the series in such an uncertain way, an ending which tells us nothing about the future, or what is to become of our beloved characters. To me, the element of wonder is exciting and all but this series is extremely definite and the ending should've been the same way. You like Oz? This is definitely the right series for you.
Purchase Location: ~I received a copy from HarperCollins NZ and willingly reviewed it~
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Recommended for: Fans of retellings.