The Mossheart's Promise delivers a cozy, creepy, hopeful story about a world that exists entirely in a terrarium - a world that has been slowly dying for some time as mold takes over. Our main character Ary, a twelve-year-old fairy, works as a mold scraper to try and salvage food for her fairy village. When Ary's mother begins to fall sick from the mold, Ary will try to step in her retired hero Gran's shoes and venture into the Gloom and Underground to try and save her. She'll uncover the truth about the terrarium she lives in and embark on an epic quest to not only save her mother, but the entire world too.

I love reading middle-grade novels, and this one was a great read! Ary's story includes lessons of compassion, second chances, and hope that I think will be really helpful for middle-grade readers. The atmosphere of the terrarium was where this book really shined for me, and as Ary ventured deeper and deeper I was filled with a sense of dread at what creepy crawlies she'd run into. The cast of characters is also great (ily Shrimp) and I think a second book where we can really flesh them out will do wonders. I think the adventure the book is leading to in the sequel (thank goodness for duologies) is going to be even better and I'm looking forward to continuing on with Ary & her pals!

Thank you to NetGalley and the publisher for providing an ARC in exchange for an honest review!

Exquisitely imaginative, but there is an epic ick factor that I couldn't ignore in reading the graphic descriptions of the mold epidemic. Maybe a little description of the mold species would have made it feel vaguely more educational and more akin to the fantastical overlapping with the world we know. That being said, I was riveted by the story and its well-developed cast of characters.

This book was well written, but I found it long winded and I didn't care for the main character. I did appreciate the way her self doubt and growth is portrayed, but I felt the story could have been more compact and concise. I also did not enjoy all the bugs in the story, but It would be a great story for anyone who does love bugs! I also felt the death of the environment was portrayed well and this is what kept me reading till the end.

I would suggest this book for anyone who enjoy bugs, the environment, the possible loss of a home world, friendships and family and learning to love oneself.

I received a free E-ARC from HarperCollins Children's Books, Balzer + Bray.

<b>Thank you to Harperteen/Balzer + Bray, the author, and NetGalley for providing this eARC in exchange for an honest review. This book will be released on September 5, 2023.</b>

<i>[M]aybe this was how the journey of every hero started—not with a grand prophecy, but a few scared people realizing it was time to do the right thing, not because they wanted to, not because they were ready, but because no one else would.</i>

Mold has taken over Terra, and when it comes for Canary Mossheart’s mother, too, she decides to defy her hero Gran and find a cure. But what Ary discovers instead is that the fairies’ home wasn’t meant to last—it’s a terrarium they were meant to leave a century earlier. Even worse, her Gran knew this and, instead of being the hero all of Terra lauds her as, kept it a secret and doomed Ary’s generation to decay. Now it’s up to timid Ary to keep the Mosshearts’ promise and find a way out.

That quote up top is the heart of this book, and the reason I fell so deeply in love with it. But a close second is the way <i>The Mossheart’s Promise</i> handles legacy and failure and righting wrongs. Both are story elements I’m obsessed with, and the way they’re executed here is phenomenal. It’s hard not to relate to Ary, whether it’s her resentment at growing up in her grandmother’s shadow, her reluctance to become a hero herself, or her anger that the task of saving the world has been left to her generation—to children—because those who came before her left the job unfinished. I also, though my feelings towards her are more complex, really loved Gran. She is an imperfect adult who has made huge and costly mistakes, and yet watching her become <i>the</i> Wren Mossheart once again was extremely powerful. Every single time I cried reading this book, it was because of Gran. It’s also impossible not to connect with the other characters, all of whom have such distinct personalities and are such a fun cast. Not to mention the sheer brilliance of the story’s concept and the dark and claustrophic but somehow whimsical atmosphere of Terra and the Underground. This is a book that doesn’t sacrifice adventure and spirit for the themes; they’re inextricably combined in one glowing tapestry.

Luminous and grimy and full of hope, Mix’s middle grade debut is inspiring and inventive, and something that I’ll cling to for a long, long time. I can’t wait to read it again and follow Ary, along with her friends, out of the Gloom.

(Plus, naturally, I’d die for Shrimp.)

If you crossed City of Ember with Nausicaä of the Valley of the Wind and threw in some fairies, you'd get The Mossheart's Promise. I've been intrigued by this story since I read the first official blurb and was thrilled to get an advanced reader copy to review. Unfortunately, the book did not capture my heart as I'd hoped it would. There is an overarching bleakness to the story, with rare occurrences of humor and hope. And there was brutalness, too, with young fairies growing their wings only to have them cut off and ground up, the magic within contributed to the rest of society where most of the population worked themselves to the bone and were left hungry, while other starved creatures in the gloom were left to fight another to the death. There are also frequent mentions of horrible scars crisscrossing the limbs of many of the older fairies and hints that not many survived the battles, suggesting old wars that did not go well. This is a bleak, brutal story that could be horrifying to young readers, rather than one which inspires hope.

As I was reading, I was strongly reminded of books I've read before, to the point where it became distracting. The "the city is dying but those in charge are hiding it from everyone else they're exploiting" themes are eerily similar to those in City of Ember, all the way down to the concept of the entire civilization/city enclosed in a world-within-a-world which is about to run out of time, and someone knew about it but didn't do anything to alert the others but now it falls on the shoulders of two twelve-year-olds to escape the city and do something about it. And the Mayor is corrupt and is forcibly maintaining the status quo, giving more to those in power and keeping the poor under their boot heels. Because of this, Mossheart felt far too similar to stand out as a fresh new take on this type of dystopian/environmentally themed story.

As an educator, there are other books with similar themes of generational trauma, of unlearning the lies you’ve been fed and re-learning the truth, and discovering that kind compassion is often greater heroism than brute strength that I would reach for before suggesting this book. It is unfortunate, as the concepts are intriguing, but unfortunately the execution fell short.

A rich fantasy that managed to surprise me with its ability to scoop me up and make me care. My first thought reading the description: fairies, bugs, a quest to save the world . . . it didn't really give me high hopes. But this is the story of a quest gone wrong, of prices too high to pay. Of betrayal and redemption. Surprisingly dark and with high stakes, this story is ultimately satisfying and leaving me intrigued to see what happens in the next story. Well done.

I really enjoyed the premise of this book, but I find reading on an e-reader hard sometimes. If this had been an audiobook, I know I would've gobbled it up a lot faster.

The main character is likable, and this fantasy world is dark and dingy. It really makes you feel like you're in the terrarium with the characters, struggling to overcome the rot and decay.
I really felt bad for the main character because she doesn't really know anything about her world, except that it is dying. She has inherited generations of trauma and must undo it all starting with almost no knowledge of what happened before her time. I think this makes her likable, but also this book is definitely for older middle-grade readers who can pick apart complex problems.

Thank you to NetGalley and Harpercollins Childrens Books for an Advanced Reader's Copy in exchange for an honest review!

This book is such a unique Middle Grade novel! Picture a world where fairies and insects live together, allying or fighting with one another and always grappling for survival in a moss-covered agricultural world and fighting a mold disease that can wipe out entire populations. Now, take that world and put it in a terrarium where these creatures unknowingly live. NOW, have a select few inhabitants of this world discover the truth that they're living inside a terrarium that will meet its demise in just a few days unless they can escape, and you have the overall gist of The Mossheart's Promise.

While this book is an epic adventure, it focuses in on a few scrappy lovable unlikely heros, particularly Ary Mossheart. Ary has grown up in the shadow of her grandmother who once went on an epic journey to save their world from the mold disease - the very same disease that has now returned and is threatening the life of Ary's mother. It is with the intention of saving her mother that Ary leaves her town, but she discovers much bigger secrets and is more or less forced to undertake an even bigger quest - saving all the inhabitants of her world.

I did feel that some of the scenes and language were a bit too repetitive. Ary is a reluctant hero grappling with her new knowledge and her bitter relationship with her grandmother, and these are huge aspects of the book; however, I felt that they could have been explored thoroughly without almost identical passages of inner thoughts in multiple chapters. I also had a really difficult time picturing some of the scenes while reading, especially at the end. There was more than one point in this book that I felt very confused, and I never did get answers to all of my questions, but I can see that this book is being set up for a sequel.

All in all this is an excellent adventure/sci-fi/fantasy epic quest that kids will love! Grades 5+

Thank you NetGalley, Harpercollins Childrens Books and Rebecca Mix for providing me with a copy of A Mossheart's Promise for review.

4.5/5 rounded up - Available 5 September 2023

This is an outstanding middle grade fantasy book. I loved it. Stick with me here, it is as if Mix went to a writing class/group and the writing prompt was 'terrarium fantasy' and BAM! A Mossheart's Promise was born.

Canary is brilliant. She is the perfect MG MC with a nice blend between the Chosen One and the Reluctant Hero tropes. I always believed in her and I always wanted her to succeed just because of the kindness that she kept throughout her journey.

The ragtag mix of friends/found family trope is also beautiful. I loved what each side character brought along and the journey that each of them took with our MC, Ary.

I also think that we need to highlight how the queerness of this story is presented. The normality of heterosexual attraction for tween characters is rampant throughout sooooo much MG and young readers material. This story presents the same level of 'MC stunned by beautiful/hot/cute character' as any heterosexual literature but just does it beautifully in a way that allows a young queer reader to have their love interest moment like everyone else. There is no discussion or exploration as to whether homophobia exists in this fantasy world and so I will choose to believe that it doesn't :)

The Mossheart’s Promise is an absolutely enchanting story that your young reader will go back to again and again. Ary is the perfect protagonist.

"From New York Times bestselling YA author Rebecca Mix comes the first book in a breathtaking middle grade fantasy duology about a young fairy who has always lived in her heroic grandmother's shadow, but now must step up and embark on a quest to save her mother from the ever-creeping mold overtaking their world. Perfect for readers who loved Brandon Mull's Fablehaven, The City of Ember by Jeanne DuPrau, and Endling: The Last by Katherine Applegate.

The mold takes all.

Twelve-year-old fairy Canary Mossheart knows this better than most. A few years ago, the mold took her papa, and even her famous, former-chosen-one Gran never found a cure. So when Ary's beloved mama falls ill, Ary decides it's taken enough. Armed with only a bucket and a prayer, she sneaks out to find a magical, underground lake whose healing waters are straight out of Gran's adventures.

But when Ary gets there, the lake's bone dry, and instead of healing waters, she finds a terrifying secret: Her entire world is actually trapped inside a giant terrarium - one they were meant to leave centuries ago. Worse, Gran knew and hid the truth, dooming Ary and her generation to a dying, rotting world.

Now, allied with only her doomsday-obsessed frenemy, a timid pill bug, and a particularly grumpy newt, Ary has one week to unravel the clues and find a way out of the terrarium - or they'll be trapped for good."

Yeah, being trapped in a terrarium, especially one that I'm in charge of, would be a very very bad thing.

Thank you to NetGalley and the publisher for granting me free access to the advanced copy of this book. A fun and whimsical middle grade fantasy that also adeptly deals with mental illness.

This was interestingly described and detailed. The world sounds fascinatingly whimsical with a touch of darker undertones that I enjoyed even if it’s suitable for children with things being a little more black and white. It’s a slow read I’ll admit with not much pull until close to the end, for me. I didn’t come back craving more every time I put it down but I didn’t necessarily expect myself to. This is definitely a book that younger me would have found awe-inspiring so I can safely say it was still a great read!

When 12-year-old fairy Canary Mossheart sets out in search of a cure for the mold that is eating her mother alive, she makes a horrifying discovery: her entire world is actually trapped inside a giant, rotting terrarium... one that her people were supposed to leave 100 years ago. Even worse, Ary's grandmother – once the town's chosen-one – knew the truth about the terrarium, and lied.
Now, Ary only has five days to find an exit. Will Ary and her ragtag group of allies be able to escape before their world is doomed?

Middle grade is not usually my genre, but I was completely captured by Rebecca Mix's The Mossheart's Promise, and found I had trouble putting it down.

The Mossheart's Promise is a darker middle grade fantasy following young heroine Canary "Ary" Mossheart. Ary's world is dying – every year it's harder for the fairies to grow food, find clean water, and the deadly mold illness occurs with more frequency. When Ary's own mother is stricken by mold, Ary knows she has to do something, even if her own grandmother tells her it's useless to try. Ary journeys beyond the safety of the wall to find a cure.

Once over the wall, Ary's preconceived notions about her world are quickly proven to be wrong. What else is the fairy leadership lying about? And when Ary discovers their world is a dying terrarium, and her own grandmother's lies, she has to rely on would-be enemies to help save her family and the rest of their world.

In a lot of ways, Ary is the reluctant heroine, but her reluctance is ground in reality: she's just a kid – how much is she expected to be responsible for? This is a recurring theme that really grounded her character and the story for me.

One thing I've also really appreciated about Mix's writing so far is the way she deals with mental illness in her characters, particularly trauma or anxiety. Her characters might have abilities, but like real people they're uncertain about what they should do, and afraid to do things despite knowing they need to do them. Here, you won't find a pre-teen that is totally prepared to save the world, and I think that's one of Mix's strongest traits as a writer.

I was totally sucked in to the world of The Mossheart's Promise: it's bleak but engrossing exploring a dying world inside a terrarium. Comparing the scale of their conflict and all the different subcultures, versus the actual size of the terrarium, (teeny tiny), it makes for a fascinating setting. In the best way possible, it reminded me of being a kid: spending time in nature, catching tadpoles, bugs and snakes in jars (they were released, thanks for teaching me right, mom!). Reading this book was a nostalgic reminder of my childhood imagination.

I can't say I had any real complaints with this story, other than that there were a couple of slower moments, but largely the plot was paced well. Combined with an investment in lovable characters, a found family element, and a darkly beguiling world, The Mossheart's Promise was a delight to read. I look forward to getting my hands on a final copy, and reading the upcoming sequel!

The Mossheart's Promise was very much the Underland Chronicles meets The City of Ember and I loved every page of it. Yeah, just pretty much everything about this book. There were so many quotes/passages I highlighted in my kindle. Cannot wait for book 2!

4.5 stars. Middle grade emotions are just something else. Themes of this book include generational trauma, choosing yourself, the importance of diversity, and exploration. Everyone's been comparing this to The City of Ember and Gregor the Overlander, and you can't really get a better comparison than that.

What I liked:
- Mold and bugs are something we can all relate to. Our world is falling apart, but it's on a slower scale than Ary's. This story takes fears of rotting that pervade everyday life and make it the end of the world in such a fantastic way.
- There were fantasy elements, but they weren't explained much, which kept the story moving, and it really worked for me.
- Found family!
- Stories about ex-chosen ones are kind of having a moment, and combining that with the strange relationship with grandparents is absolutely brilliant.

What I had mixed feelings about:
- It's just a little too close to both its influences. The first half is The City of Ember with fairies, and the second half is Gregor the Overlander if he failed and had a granddaughter.
- Genocide in middle grade books is always a tough topic to wrangle.

I just loved the world of this book. The dying terrarium with mold sucking the life out of the ground and infecting/killing little fairies and creatures alike is such a fantastic premise, and Mix definitely ran with it fast. Mix was unafraid to show the horror and creepiness, displaying it fully and unapologetically. I have no doubt in my mind that this will probably give kids nightmares after they read it, but they'll love it, all the same.

Ary was also a very delightful protagonist. Scared as all hell but still brave and kind, even to those who hate her because of her grandmother. She doesn't want to bare the weight of saving broken world she was inherited by generations before, a feeling people my age know very well, but it is the love she has for her mom and her new friends that drive her forward. The side cast are also amazing as well, specifically, for me, Sootflank, because the old, grumpy lizard is too enduring not to love.

The only slight irk I have against this book is how repetitive it gets. Ary's thoughts loop around her not being her grandmother and how she wasn't a hero, just a girl wanting to save her mom. I know that is all she could think. given her situation, but reading it over and over got old by the midway point of the story. Luckily, this didn't dampen my enjoyment too much; it's just a slight annoyance.

All in all, a really great read that will certainly traumatize a generation of readers. I cannot wait for the sequel and see what happens next!

I would like to thank Netgallet and Harper Collins for giving me an ARC for The Mossheart's Promise.

Enter Terra, home of the fairies who are on the brink of destruction from mold. Ary Mossheart, the granddaughter of the chosen One, goes in search of a cure once her mother is infected by the mold. She comes to find out that the world she calls home is actually a rotting terrarium that they should have left decades ago and her chosen one grandmother knew all about this and had lied about it. Ary only has a short time to find the exit before everyone is trapped forever.

This made me so happy to read. It combined Gregor the Overlander with fairies which is just chefs kiss to me. It was creepy especially when the book goes into detail about how the mold takes over. Definitely nightmare inducing. Ary is a great protagonist. She doesn't see herself as a hero but she is the only one who can save her mother. You feel her fear over this possible loss and then her anger when she learns that her Gran could have ended this years ago and didn't.

Sootflank is definitely a favorite character. I tend to really like the grumpy characters who you're not for sure they are on your side or not. Shrimp is adorable and must be protected at all costs. Owl needs to be bundled up and giving all of the hugs.

I give this 5 out of 5 stars. I could not put this down. It has great writing, captivating imagery, and amazing characters.

Absolutely the best middle grade I’ve read all year so far. Becca did a wonderful job of destroying my soul with the characters. Especially ones that were unexpected.
10/10 would recommend this wonderful book.

Wow, wow, wow! This is at the top of my list of favorite books I've read this year so far. It's one of those reads that you keep thinking about after putting it down and you both HAVE to finish it but you also don't want it to end.
The writing kept me on the edge of my seat the entire adventure and the world-building and lore had me wanting more from this universe!
Overall, I thoroughly enjoyed this story and will be recommending it to my friends!