Undead Oaths

Undead Gods #2

by Caitlyn Battelle

When a mortal woman makes a deal with a god and the fates come out to play... Can she change what has been woven, or will the mistake of a god be the ruin of them all?

Elysia Parker is furious. After making a deal with the god of the dead to find his talisman, she's horrified to learn her mortality is on the line. Still reeling over being doomed to share his throne, Elysia is devastated when she finds out the soot destroying her kingdom is slowly killing her sister.

Working with the god who set her kingdom's destruction into motion, Elysia struggles to trust him or her changing feelings. But with the fates blocking her from finding the talisman, Elysia fears both her kingdom and sister will fall.

With the spread of soot threatening the entire mortal realm, can Elysia defy the fates and find the talisman in time?

Genres: Fantasy, Romantasy, Ebooks, Romance

418 pages, Kindle Edition

Published January 5, 2026

About the author

Caitlyn grew up on faeries, folklore, and late-night reads. Her dream is to write fantasy stories that will keep you turning the page long after everyone else is asleep. She lives with her partner, tripawed floof of a dog, and the world's friendliest tuxedo cat. If you can't find her, then she's probably escaped to the forest, but will provide updates from @caitlynbattellebooks on social media.

Reviews

[Erika · Rating 5 out of 5]

As much as I enjoyed Undead Gods, Undead Oaths took my breath away. The way that Battelle breathed life into her characters, captured my interest with her unbelievably descriptive details, and had my heart racing to finish this story are unmatched. I schemed with Elysia, I yearned with Aidan, I protected with Crusher, and loved unconditionally with Beatriz. I cried and laughed multiple times while reading, and am still shocked with all of the ways this book (pleasantly) surprised me. If you're looking for a unique magic system with mythological elements and a can't-put-it-down vibe, this book is for you.

[Marissa · Rating 5 out of 5]

Caitlyn Battelle’s “Undead Oaths” is a fantasy romance and the second book in the “Undead Gods” trilogy! A Hades and Persephone-inspired tale, Elysia Parker continues to thwart the fates, save her kingdom, and resist the tempting God of Death. Please review the trigger warnings page!

Tropes: Obsessive MMC, Fierce FMC, He YEARNS, meddling Gods, found family, “MY WIFE.”

This book felt lighter than book one. Although this book confronts harsh realities, it has a sense of humor. There is witty banter, sarcasm, and all-around funny moments that made me grin and laugh in a way that helped it feel light. I was able to escape in it.

“Undead Oaths” is a retelling of the Hades and Persephone myth, and it really showed in this book! I really enjoyed the allusions and references to the myth itself, whether it was through conversation, minute details (the Ultimatum was a favorite), or events that reverberated in this story.

In terms of spice, this book sits around 🌶️🌶️.5. It was more explicitly detailed than the spice we read in book one. It is a slow-burning experience riddled with yearning and “don’t fight this” discussions that culminate in a steamy “f- it” moment, as savory as it is sweet. I’m not complaining- I was hoping Battelle would show us whose endgame 😏

Aidan’s character was fun for me; he’s witty, ripped, nerdy, and he YEARNS. He’s as much of a heartthrob as his story was heartbreaking. His eyes were blue flames that set me on FIRE! There were a lot of witty lines here regarding him, and I loved them. I also really enjoyed that Battelle reminds us that Hades is essentially the Office Manager of the Underworld, rather than the one who reaps.

All of the secrets come out of the woodwork in “Undead Oaths.” Battelle prepared readers for the realms from book one, but I loved that she practically ripped the band-aid off and showed us just how little we actually knew about the whole truth. We met meddling gods who are already getting started with their antics, and we experienced double crosses that will impact our characters' perspectives and journey.

[Rebecca ~ readinginNZ · Rating 4 out of 5]

✨ARC review✨

“Welcome home, love. I’ve been waiting for you.”

✨ Hades x Persephone retelling
✨ Slow burn that actually delivers
✨ Quests & prophecies
✨ Touch her and die devotion

Book two in the Undead Gods series picks up right where Undead Gods left off, no breathing room, no mercy, just straight back into fate, gods, and very bad decisions made for very good reasons 😮‍💨

Elysia has made a deal with Aidan, god of the dead, and this book fully leans into the consequences of that choice. There’s a quest for a talisman, prophecies tightening their grip, and a growing sense that fate isn’t something you can out-run, only argue with loudly.

“My people don’t have gods. We don’t have fates. Only their consequences.”

The slow burn here? IMMACULATE. This is patient, aching tension layered with restraint, fear, and longing. The kind that simmers for chapters and then finally pays off in a way that feels earned.

“Tell me why I can’t love you while making you rule beside me. Tell me why the idea of my devotion makes you want to run.”

Aidan is everything I want from a godly MMC. He is powerful, controlled, deeply devoted, and absolutely lethal when it comes to protecting her.

“And if you hadn’t come? I would have stolen you through a crack in the earth…Because even though you don’t see it, that’s what you deserve…love, adoration, power.”

The found family elements shine even more in this instalment, with Crusher stealing scenes like a very good undead-adjacent boy 🐕‍🦺🖤

“With all I’ve done, is there any hope for us?”

This book deepens the world, the mythology, and the emotional weight of Elysia’s journey. The romance is still a slow burn, but it delivers, and the balance between plot, character growth, and devotion is chef’s kiss.

“She honestly wants to bail. Bail on fate. Ugh, I love a reluctant hero. Best. Death voyage. Ever.”

If you love destiny, and a romance that makes you ache before it heals you - this series is absolutely one to commit to 🖤

Thank you for trusting me with this ARC Caitlyn! 🫶🏻

Chaos, vibes, and opinions are all my own ✨ please give credit if you share.

[Belinda Smith · Rating 4 out of 5]

Undead Oaths swept me under like a tide of shadow and prophecy, and I lived for every devastating second of it. 🌑🔥 This was the book where the Hades & Persephone–inspired storyline finally took center stage, and gods… it did not disappoint.

Elysia Parker had already made one reckless deal with a god — now her mortality was slipping through her fingers, her kingdom was choking on soot, and her sister’s life hung by a thread. 😭⏳ She was furious, terrified, stubborn to the bone, and absolutely the kind of heroine who would fight fate itself if it dared stand in her way. And it did.

And then there was Aiden. My favorite. Always. 🖤
Vulnerable beneath all the shadow, aching with guilt, anxious and ancient and so desperately in love with a woman who couldn’t trust him. Yet in a heartbeat, he became the dark, possessive god of the dead — the one who could ruin you with a look. And the shirtless sparring scene? I ascended. 🔥

Their dynamic was pure chaos and tension — don’t trust you, can’t stay away from you, fate is laughing at us. Every moment between them throbbed with “just kiss already” energy. 😭💋

The world was crumbling, the fates were pulling cruel strings, and the talisman stayed hidden as though mocking them. The pacing flew, the stakes soared, and I found myself clinging to every page like a lifeline. ⚔️🌫️

By the end, I was feral. Obsessed. Desperate for book three. This trilogy just kept getting darker, sharper, and more soul-crushing in the best possible way.

✨ Tropes & Vibes
🖤 Hades x Persephone reimagining
🔥 Slow burn tension
💀 Possessive death god
😤 Stubborn, furious heroine
🌑 Fate vs free will
👑 God x Mortal
💔 “I shouldn’t want you” yearning
⚔️ High-stakes quest & prophecy

If you love dark romantic fantasy, shadowy gods, anxiety-ridden antiheroes, stubborn mortals, and tension sharp enough to cut you — Undead Oaths was written for you.

Bring on book three. I’m ready to have my heart ruined. 🖤🔥 Thank you to the author for the ARC opportunity 🤍

[Kasha · Rating 5 out of 5]

UNDEAD OATHS - CAITLYN BATTELLE

I don't have the best track record when it comes to the second book of a trilogy, where these often feel like a bridge building up to the bigger and louder conclusion. That is so NOT the case with Undead Oaths.

Undead Oaths is the second book in the Undead Gods trilogy, and I feel like this is really where we see the Hades and Persephone inspiration come to life. Elysia has made a high-stakes deal with a death god, and this sends her on many escapades throughout the real world and underworld. There's so much more worldbuilding in this book, and I loved this.

However, it's the characters that really shine. It feels like each character is given a chance to develop through their own missions, forcing them out of their comfort zones and into interactions they would never otherwise have. Then there's Elysia; anxious, relatable, clever and witty, she's one of my favourite FMCs of all time.

Actually, Undead Oaths is full of female characters who are doing their utmost to sidestep fate. Even when these are characters you're not necessarily cheering on, I love this aspect of Battelle's writing. And just like book one, this book ends with a cliffhanger that will have you questioning how on earth you can be expected to wait for the third book.

Slow-burn romance - yes. Spice - yes. Satisfying story and character development - yes. Twists and turns that will genuinely shock you - YES.

Thank you to Caitlyn Battelle for the opportunity to read your amazing book.

Review score: 5/5

Release date: 5 Jan 2026

TWs: d*ath, v*olence, injury detail, s*xual content

[Tali · Rating 3 out of 5]

I feel a bit mixed with this book. I'm not the best at organizing my thoughts so I think it's best to do pros and cons.

Cons:

My main issue (this could be completely a me issue) is I don't like the MC. I think she is a violent, hypocrite, who has no ability to read people and makes set assumptions on people and takes forever to change her mind about them even if she is proven wrong.

She acts like everyone is less responsible then her but she is the one who is causing havoc. She is also a brat (not a fun brat) to people helping her. She then acts like no one really cares about her when in the first book and this one you see a group of people that show obvious concern for her well being and she come across like she is annoyed at them for it.

I think the transitions were sometimes too abrupt and I got lost a few times and had to reread a few pages to understand where and when the setting was. (This could also be a me thing)

The romance feels too rushed for what happened in the first book. With no structure or real build up it was less of enjoying hot book sparks flying and more like wondering who the heck lit a fire cracker in the middle of a Macy's. It was weird and random and out of place in the beginning.


Pros:

At a certain point I just accepted that if the MC is talking about someone I should take it with a grain of salt and I enjoyed it a whole lot more.

I love Hades and Persephone based stories in general and I thought the main plot was interesting.

I love how the setting grew from the first book and you saw more of the world.

Besides the MC I like most of the other characters, some nerdy characters and animal loving characters I flat out love and would always be excited when they were the focus.

When the POV changed I enjoyed the banter and the other characters in general. The sass from some of these characters had me laughing a few times.

I love the smart guy being dumb in social cues and the "dumber" friend being a genius in them dynamic. (For people who read the book you probably know who my favorite characters are.)

I like when things got stabby for the right reasons. Not just a random impulse violence but something that actually was fitting the plot.

I adore a certain black market boss Queen that did so much behind the scenes I wouldn't be surprised if we learned she was doing another epic thing later on.


All in all I do think its really disappointing that I don't enjoy the MC. But when I'm reading it for everything and everyone around the MC I do enjoy it. If a friend were to ask me if they should read it I would say yes and would want to have a long conversation after.

I am curious to see what happens next and how the characters will continue to change each other. So while I may have mixed feelings over all I will be keeping an eye out for the next book so see what happens next.

[Julie · Rating 4 out of 5]

Undead Oaths kicks off immediately after the conclusion of Undead Gods, no recap or anything so it's a good thing I just read the first book! The deal made with the god of death is the plot and I am here for it!

This book's trope is now a new obsession: Hades and Persephone reimagined. The god of death yearning for a mortal fated to be his. Say less. And give me more!

"Welcome home, love, I've been waiting for you."

Umm. Excuse me sir. Why am I feral for "where is my wife?" energy? The god of death with shadowy soot magic is a nerdy accountant type always writing in his ledgers is just too adorable. And his eyes burning with blue fire? Ok someone do some character art.

With the deal to find death's talisman and save the magic I expected epic trials and while Elysia went through some things, it wasn't exactly how I expected it to go. In fact, there were twists and betrayals at every turn. The fates sending cryptic assignments and those going dangerously awry and yet working out in exciting ways. 

Elysia continues to have to prove herself worthy of this "death voyage" and at every turn has to decide whether to save herself or choose others, constantly landing at death's door, literally and figuratively. 

But trust is something she still struggles with and is a big part of her character arc and voyage in this book. Rightfully so, since Aidan is responsible for everything wrong in Elysia's world. Plus he does the annoying thing of keeping secrets from her. So many problems can be resolved if people would just talk to each other. But then we wouldn't have the slow burn and death's yearning. 

For the pacing, I will say the first half of the book kind of took some time to get somewhere, with a few high stakes situations but mostly waiting for clues to appear for this death voyage. Then the final maybe third of the book was absolute chaos with the aforementioned betrayals, double and triple crossings, and more surprises. I feel like Princey boy redeemed himself a little with his own journey, though that is still to be continued. I was a bit let down with one of the reveals only in that I felt like this person should have been recognized as who they were in life. The ending though was exiting and emotional and there's no telling when the next book will be out! 

[Megan O'Brien · Rating 4 out of 5]

4.5 stars for a stellar sequel that takes Elysia across realms both living and dead (and both giving me life and killing me all at once)!!!

When we ended book one with Elysia on deaths door ready to make a deal with Aidan in the underworld, I thought I had some ideas of what he, the quest, her feelings about the matter, and the underworld may be like- and boy was I wrong (in such a good way)!! I should’ve known that our tough independent girl would have had a LOT of thoughts about Fates trying to step in and make decisions about her life without her input and that nothing would come easy for her. Once she got past her lil tude and started embracing the quest and embracing her choices still left to her, including to have a life, her dogged attempts to change the Fates got that much better! Bringing in friends and foes from above and below, and mixing in some gods and goddesses, Elysia sets her path and girl gets it done!!

I love and hate our girl, she can be a little hard to handle but that’s all because she was told she was hard to handle in a world without magic. As she learns to soften (just a little okay, she doesn’t have to change that much) and let people in, she becomes a stronger version of herself that will make for an unbeatable queen of the underworld. Sweet anxious Aidan just absolutely won my heart this time. A god by design and not choice, he has found his own ways to assert control and understanding over a world that makes no sense - and is committed to his people (his person) like no one’s business. Even good ole Topp Blatz (who must be full named) gets a full arc here, having to understand what it is to be understood as a person and not a prince, to look and think deeper (honestly he’s giving fiyero) at other people and situations, and has tough choices to make if he is to be the maybe future king of Kava.

What a fantastic second addition to the series, now how quickly can we get book three?!? Thanks so much to Caitlyn Battelle for a chance to read this in exchange for an honest review. You are wonderful!

[butterfly_reading_effect · Rating 5 out of 5]

What a book! Often in a trilogy book two is a bit slower but not this one!
This book had me hooked from page one till the last page.
The hades and presephone theme is much more evident as our god of the dead takes a much more prominent role in this book.
His and Elysia relationship is an extremely gorgeous slowburn full of yearning and tension.

The inner dialogue of Elysia is one of my favorite things
of this book, she is so witty, funny and downright honest. While being full of plot twist, oaths, deals, and betting it will leave you guessing and wanting to keep on reading, regardless of your bedtime.

There is a lot of character growth both the main characters but also the side characters- i actually love
Beatriz now and might not push Topp off a cliff just yet,
but jury is still out.

The spice is well worth the anxious tension filled wait and is done extremely good and full of emotion on not just straight up physical, i loved the raw unfiltered
moments it created between them as well.
Also there is cute dogs that turns into beast
if you mess with Aidan’s lady should you need another reason to read!

thanks for the arc i will now start to stalk your socials for any crumbs about book 3

[RiverFiend · Rating 5 out of 5]

Wow, just wow. In my review for the first book I thought the pacing was a bit slow. There is NONE of that in this book. We hit the ground running and you are not going to drop this book til it’s done.

A deal with the devil, or undead god, can have some major consequences. The quest for the talisman isn’t so simple when we realize fate isn’t up to chance in this world.

This was a MAJOR slowburn, and the crumbs were delicious! Combine “where is my wife” with “who did this to you” and you’ve got yourself an Aidan. Strong, devoted, and loyal to a fault. He’s full of secrets but seems to only want the best for Elysia.

I really enjoy how he is humanized as the story progresses. Of course he lashes out when the fates changed his, well changed his fate. Forced to end the life you loved early to do their bidding, its more understandable how things unfolded.

The banter and steamy moments between Elysia and Aidan couldn’t have been better. Watching her learn to trust him and his intentions was *chefs kiss*

Overall I loved this book and I couldn’t put it down!

Thank you to the author for this ARC!! All opinions are my own.

[Persephone · Rating 5 out of 5]

I was chosen as an ARC reader for this book. I had not read the first one before applying. My name is Persephone and have always felt called to read books based on my namesake’s story. Readers…this one is in my top three. I read it so fast and ended up reading it again. The spice level is just right. The way the FMC and MMC are written together truly reminds me of how I’ve always felt Hades and Persephone to be. The world building has been some of my favorite I’ve read in a long time. And the little twists towards the end? So much fun!

Minor spoilers ahead:
The death voyage concept matches so much of what we experience in life. We feel jerked around by The Fates to earn what we know is ours but can take what feels like a lifetime. But ultimately we decide what we want and when to get it.

[Olivia Renner · Rating 5 out of 5]

This has been my most anticipated read of the year, and I devoured it in a day 😭

This was a wild ride that kept me on my toes and made it impossible to stop reading. Picking up where book one left off, I was immediately sucked back into the world.

Elysia has lived a life of servitude, with people manipulating and betraying her. The character growth and arc in this book are so satisfying. Feminine rage is my favorite genre 🙂‍↕️ But beyond that, she grows in ways that are healthy and new, despite what she's been through. And it was so fun to go along for the journey!

Also 👀 "my wife" I was deaddd. Squealing and kicking my feet.

Aiden is just what Elysia needs. Those two and the way they challenge each other, the BANTER 🤌🏼 and oh my god at the end 😫 I loved it.

The plot twists, the fates, all the sibling drama!!! So well done and fun to read. As someone who has many siblings, it was fun to see those dynamics throughout.

Favorite parts (spoilers galore):






When she first gets to the death realm. the intensity was just 🤌🏼
Elysia snapping that guy with her abilities stealing his like GO OFF 👏🏼
Gage turning into a cat 😂
After Elysia's foot is broken and Aiden said he listened to her breathing all night and to let him help her AHHHH
"My wife" !!!!!!!!!!!!!
Elysia finally saying she'll stay with him and the gold that matches on their arms 😭
Crusher 🥹
LINA MENTIONED (i love that raccoon)
Every time Aiden had to comfort, help, and save Elysia's ass 🙏🏼
Aiden being able to leave the death realm!!!!!! (plus Topp having to witness it hahaha) And when he said "focus, sweetheart" to Elysia's soul 😂😭

Anyway. I loved loved LOVED this book. It's been months since I finished a book so quickly 🩷 Reading slump cured 🙏🏼

[Nicola Robinson · Rating 3 out of 5]

I was very lucky to receive a digital ARC of this from NetGalley - so thank you. Here is my honest review.

So… I didn’t realise this was a second book. So I don’t know how much that matters that I haven’t read book one…

Whilst the premise is exactly the sort of thing I LOVE; enemies to lovers, slow burn, tension, a quest and high stakes, a retelling of a mythical story… this just didn’t do it for me.

I don’t know if this should be classed as YA (other than the spice) because the writing just felt super modern and conversational for what’s supposed to be Gods so it just didn’t feel… right to me. They sounded like American 20 year olds cast as high schoolers.

Aiden (or Hades) is the best part of this whole book. His character is the best - the way he speaks and behaves… feels right.

Furthermore - there are way to many side characters that are incredibly tough to keep track off (easier if you’ve read book 1?) and their names just don’t feel right right. Prince Topp? Rollie? Come on!

So… sadly… this was not for me :( I did not enjoy it as much as I expected.

[nooked_ina_book · Rating 5 out of 5]

This is how you do a second book and Caitlyn blew it out of the water! The foundations from Book 1 were such a wonderful launch for this book to take off from and there isn't a single thing I disliked.

Every single character had their own place in this book while blending together seamlessly together. The character development is so realistic, so relatable, and pulls at your heart strings. The emotional struggles they all endured and overcame had me in tears, both of joy and heartbreak. Elysia and Aidan are my new favorite book couple.

The plot of this book is so unique, such a wonderful twist on games and trials and I ate. it. up. The Gods, fate, and forces of brute will and determination all clash in a high stakes ride that had me turning page after page. The slow burn and yearning subplot is a true slow burn that was as delicious and devine as can be.

I received this book as an ARC reader for my honest review and that honest review is I am utterly obsessed with this series. Caitlyn Battelle has created a world I am so happy to have found and I will be sitting here anxiously awaiting Book 3.

[Kaitlynn Dykman · Rating 5 out of 5]

Caitlyn Battelle may be just an “indie little potato” of an author, but her world building and character arcs are “topp” notch (sorry I can’t resist a pun XD). I’m loving the intrigue left off at the end of this book (although now I freaking have to wait for the third?!?) and I love being surprised in a plot- as someone who reads too much, that doesn’t happen a lot! Can’t wait for more front and center Aidan and Elysia in the next book ;)

[Rachel C · Rating 5 out of 5]

Couldn’t put this book down! I loved how it picked up where the first one left off. The world building between the gods, fates, and mortals was very well written and quite interesting! I also loved the dynamic between the main characters.

[GenXBookBestie · Rating 4 out of 5]

Undead Oaths had me questioning my morals, my sleep schedule, and why I’m so easily swayed by a man who quite literally says:
“The Fates marked you for Death, and I am Death.”
I folded. Immediately.

This book is soaked in dark magic, dangerous promises, and shadow daddy energy that lurks, watches, and absolutely does not ask permission. The MC'S aren’t just enemies to lovers, they’re brooding, oath bound, and saying things that should come with a warning label and a glass of water.
The romance simmers with that slow, lethal tension where every glance feels like a threat and every touch feels like a bad decision you’d make twice. The banter snaps, the stakes are high, and the vibes are deliciously unholy. I was hooked, feral, and emotionally invested in ways I refuse to explain.
The cliffhanger left me wanting more! More danger, more time drowning in the shadows with Death himself. And honestly? Book three can't happen soon enough.

Final thoughts:
✔ Shadow daddy energy
✔ Oaths, death, and morally questionable devotion
✔ Would absolutely answer the call if Death whispered my name
Would recommend to anyone who enjoys dark romantasy, lethal love interests, and the sudden realization that yes, apparently this is your type now.

[The Fantasy Bookwyrm · Rating 4 out of 5]

ARC Review - 4.5 stars
Undead Oaths was absolute pleasure to read. The worldbuilding is rich and atmospheric, with high emotional stakes and a constant sense of looming danger.
While the pacing slows in places due to heavier worldbuilding, the story remained engaging and layered. If you are after a new romantasy with a flavour of Hades and Persephone, you love a good side character and rich world building. This book needs to be on your TBR.
Thank you so much NetGalley and Caitlyn Battelle for allowing me the opportunity to immerse myself in this amazing universe.

[savage_book_review · Rating 4 out of 5]

*Please note, I was provided with an ARC version of this book by the author and am voluntarily leaving an honest review*

I've been looking forward to reading this book as it's where my beloved Hades and Persephone lore moves to centre stage in the story. And on that front, it certainly doesn’t disappoint! The characters are somehow both completely inkeeping with what you expect from this type of story, but at the same time with a unique spi that leaves them all feeling fresh and different to anything else you've read.

Aiden is far and away my favourite character (to the surprise of absolutely noone). He feels so much more vulnerable than other Hades characters, with guilt chewing him up over his past decisions, an anxiety-riddled brain that spoke to me on so many levels, and the yearning for Elysia for hundreds of years just making him a total sweetheart! And yet, there are the flashes of the possessive, dark, sexy God of the Underworld shadow daddy that remind you exactly who he can be. Plus, there's a shirtless sparring scene. Excuse me while I melt at the whole damn package!

Elysia was harder to pin down in this book, mainly I think because it felt like she was backed into a corner at every turn, and had to dance to other peoples' tunes rather than having the freedom to make her own choices. There's just something about her I can't quite trust, particularly whete her feelings for Aiden are concerned; the development of their relationship from her side of things did come across as a bit forced. There's no drnying her physical attraction to Aiden; that's baked in to the writing really well, but I was less convinced by her emotional connection to him. Which has me worried!

There is an abundance of secondary characters to follow too, both in the Deathlands and in Kava, and with all of them we have what feels like too much and not enough at the same time. I am still completely unsure about how I should be feeling when it comes to Prince Topp; we see him on his own quest and, just when you feel like you might have his measure, something happens to twist him up in your mind all over again. I just need to know more about all of them!

Turning to the plot, while I love the premise and the imagery conjured by the author's style, the book as a whole felt like it zipped by at 100mph, especially when compared to the pacing of the previous book. As a result, much of the action and a lot of the crucial scenes felt like they lacked depth, which had the knock on effect of leaving me feeling like I had somehow skipped pages and missed important details. Conversely, there are a couple of twists, reveals and surprises that are dropped on the reader in casual conversation. This isn't a bad thing in and of itself, but to some extent I fell like they deserved a bigger build up or a full blown 'mic drop' moment. It's abundantly clear that the author has this story in her mind with crystal clarity, but somehow it's not quite fully translated onto the page. Nonetheless, if you allow yourself to be transported and just let the story wash over you as you read, the broad strokes allow your own mind to sketch in the details in the same vivid colour as the author's descriptions allow you to see the beauty, squalour or darkness of the settings.

So basically, my usual battle cry of 'more, more, more!' bears repeating here. I'll definitely be reading the third book, and living in hope that the author has some glorious bonuses up her sleeve to fill in some of the gaps!

[BrekkfastAtTiffanys · Rating 5 out of 5]

Book Title: Undead Oaths
Author: Caitlyn Battelle
Genre: Fantasy
Publication Date: 1/5/2026
Format Reviewed: Ebook-Kindle
Overall Rating: 5 stars! I would read this book again or buy a shelf trophy copy and recommend to others! ★★★★★
Spice Level:
(Rate 1–5 peppers, where 1 = Mild/No Spice and 5 = Extremely Spicy)
Spice Rating: 🌶️🌶️
Summary (No Spoilers):
This book takes off right where Undead Gods ends. Elysia (FMC) makes an oath/pact with Aiden (undead God) to help heal her kingdom from the King who destroyed the magic that once filled the kingdom. Elysia struggles with a lot of inner conflict between trust and love vs self preservation. She makes a lot of mistakes along the way and I just love how her character develops in this story! Aiden is such a vibe with so many green flags but is also the most imperfect god. He is everything that Elysia doesn't know she needs and I love this for them. The first half of the story builds and builds and there is so much tension and slow burn between the two MC's. The second half I devoured SO fast! There were moments I wanted to yell at Elysia and throw the book because I was so invested in this story! The side characters were the perfect amount of antagonist and morally grey. There were no loose ends in this book and I closed my kindle afterwards feeling so satisfied with how it ended! OBSSESSED!!!!

What I Loved:
- Pacing
- Plot > Spice
- Banter
- Side Characters
- TRUE love/hate between FMC and MMC

What Could Be Improved:
- I wouldn't change a thing about this book!

Spice Breakdown:
This book has a couple open door spice scenes and there is definitely yearning and slow burn tension! The spicy scenes were so well written. I feel like by the time you get to the first spicy scene, you are emotionally invested in the character so it doesn't feel smutty or cheesy at all. I would argue that not having them in the book would be a travesty to the story! I went back and forth between 2 vs 3 peppers because the spice wasn't over the top, obscenely graphic or smutty but does have enough detail in it that could make non spicy readers blush lol.

Who Should Read This Book:
Fantasy, world building, high stakes, emotionally and morally grey characters (literally ALL of them lol)

Favorite Quote/Blub: "F**k it." - Aiden
(My enemies to lovers and slow burn book girlies will know exactly what I am talking about here. When I read this, I was the reader equivalent of someone cheering at the TV for a football team getting the winning touchdown lol)


Final Thoughts:
I will shout from the roof over a fantasy/romantasy book done right with my fav tropes weaved into it (enemies to lovers, slow burn, forced proximity, morally grey). If this is your jam, immediately add Undead Gods (#1) and Undead Oaths (#2) to your TBR!

Would I Read More by This Author? YES YES YES!

[MelReads29 · Rating 5 out of 5]

It’s not often that Book 2 outshines Book 1 in a series, but Undead Oaths absolutely does. This was a five-star read for me. If you haven’t read Book 1 yet, stop here and go grab it first. You’ll want the full context, and continuing will spoil some key moments.

We continue following Elysia, our main female character, who possesses magic in a kingdom where magic is illegal. While magic and undead gods exist in the wider world, the kingdom Elysia lives in has outlawed it entirely. Anyone caught practicing magic faces public execution. Elysia is part of the royal court and is poised to become queen, all while hiding her rare ability to uncover secrets. She keeps this hidden from nearly everyone, including her boyfriend, the crown prince, her friends, and her family, with the sole exception of her father.

Unfortunately, her father is physically, emotionally, and verbally abusive. Her prince is oblivious to the trances she slips into, her sister is bound to drugs, and her mother is ruthlessly obsessed with status and appearances, think Dance Moms turned up to a thousand.

Elysia begins experiencing vivid dreams and soon learns she’s being called by the Death God, Aiden. By the end of Book 1, Elysia has been left for dead by the man she loves and pushed beyond her breaking point by her father’s cruelty, takes her own life into her hands and ends up making a deal with the Deathlands God. In Undead Oaths, she decides she’s done being powerless. She strikes a bargain with Death himself in an attempt to set things right for her kingdom.

The gods in this series echo Greek mythology, with Caitlyn Battelle putting her own spin on familiar figures, particularly a Hades and Persephone, inspired dynamic. The lore is easy to follow, immersive, and thoughtfully layered without becoming overwhelming. At its heart, this is the story of a broken-hearted young woman who finally claims her identity, walks away from her first love, stops trying to appease her parents, and takes control of her own destiny. Her bargain with Death sets her on a quest to recover his talisman so he can regain his full power.

We get a heroine who refuses to die, flips fate the middle finger, and fights to fix a kingdom that has failed her. The story delivers trials, twists, and a natural progression that never feels forced. There are meaningful redemption arcs, and a broody MMC who is kind, caring, possessive, strong, witty, and refreshingly riddled with anxiety.

If you enjoy Hades and Persephone, inspired retellings, epic quests, enemies-to-lovers (with a touch of stalker tension), fierce determination, and strong writing, this series is for you. I cannot wait for Book 3.

Thank you to NetGalley, Twelfth House Publishing, and Caitlyn Battelle for the eARC.

[Peyton · Rating 5 out of 5]

Welcome to Kava, where the magic has abandoned the land, and the Gods have turned a blind eye. In Caitlyn Battelle's Undead Oaths, Elysia has made a deal with a God to help him find his talisman so that, in return, he can help save her Kingdom and bring the magic back.

We continue to follow Elysia as she has made her decision to seek help from Aidan, God of the Death Realm, and achieve their goal of bringing magic back. In doing so, she's furious because this deal came with some caveats that she didn't know about until afterward. Now, not only does she have to find Aidan's talisman, but now she has to deal with the news that her mortality is on the line. By taking this deal, she is now obligated to share the throne. I can see why she would be upset, but considering the events that happened prior to her accepting this deal, she didn't exactly have much time to consider and ask the questions. As is the nature of a Hades and Persephone retelling.

I found it funny how Elysia can't decide if Aidan is "an accountant who sometimes fights or a bookie who drinks too much tea." In other words, he's an extremely attractive nerd who loves to crunch the numbers and calculate the odds, yet runs a gambling house and has some of the smoothest lines that make Elysia feel a type of way. I feel like if he is ever topside, he would enjoy talking numbers with Rollie, and have a contest with Topp on who has the smoothest lines. What I loved about Elysia and Aidan's relationship is their communication with one another. When they meet, there is a tangible attraction between the two, but they each are still going through their issues to act upon it. There are still a lot of unsaid things between them, and a lot of information that they have yet to disclose to one another, but they still make time to try and be honest with each other. In the few instances that they meet, they feel more open than they have been with anyone else. Once they have accepted each other, they will do everything in their power to achieve their goals and start their life together.

It was also refreshing to follow Topp and Rollie on their adventures to help. Despite the fact that they've known each other their entire lives, they barely acknowledge one another, and now they travel with each other in hopes of helping Elysia with her tasks. I also enjoyed exploring more of Elysia and Beatriz's relationship. While they haven't had much time together in the past, going through this journey has helped them gain perspective on each other. Elysia already knows she has to find this talisman, but when Beatriz gets sick, she hopes there is enough time to help save her sister.

As with any great story, readers go through a sojourn full of twists and turns, masterfully woven and told through a complex fantasy world and characters worthy of the Fates' design. They've never been one for obeying the rules, so why should they start now. With everything the Fates created out of the way, let's see what happens next.

I received an advance reader copy of this book from Caitlyn Battelle for free, and I am leaving this review voluntarily. My intentions are to write feedback that reflects my genuine thoughts and is written with the book’s genre and target audience in mind. I aim to review fairly and respectfully, focusing on the story’s purpose.

[Alicia (weird.reads.books) · Rating 5 out of 5]

Rating: ⭐️⭐️⭐️⭐️✨ (4.5/5)
Spice: 🌶️🌶️

Undead Oaths picks up exactly where Undead Gods left off, and I’m so glad I read them close together. Having book one fresh in my mind made the continuation hit even harder. This sequel expands the scope in the best way, digging deeper into characters we already love (or love to hate) while turning the complexity dial way up.

Elysia remains the beating heart of this series: sharp, stubborn, and constantly trying to defy the fates. She’s fiercely protective of her independence, endlessly scheming, and unapologetically morally grey. I loved that she’s the kind of heroine who’s made brutal choices to survive (sometimes at the expense of others), and the book doesn’t sand down those edges to make her easier to root for. Her political maneuvering feels earned in this world, and even when book two opens in a slightly different setting, she adapts fast and proves she’s absolutely not someone to underestimate.

Her fate is tied to Aidan, the god of the Underworld, who wants to win her over without stripping her of her autonomy. And while he’s powerful and more than a little ominous, he’s also not untouchable. He has real insecurities and flaws, which made him feel surprisingly endearing. He’s our sexy, nerdy, anxious accountant god.

One thing I really appreciated about this series as a whole is the breathing room it gives its cast. Book one took the time to build the world and relationships before fully introducing the main love interest, and that foundation pays off here. The side characters don’t get shoved aside for romance. They’re allowed to evolve, deepen, and complicate the story in meaningful ways.

The romance is a slow-burn, and it absolutely delivers, but it’s only one piece of what makes Undead Oaths so satisfying. There’s also Elysia doing what she does best: plotting, outmaneuvering, and setting vengeance in motion against the king of Kava. There were definitely some “good for her” moments I absolutely loved.

If you’re looking for fantasy with characters living across the entire grey spectrum, a political/magical plot that stays engaging, and a slow-burn romance that actually pays off, pick up Undead Oaths. Just make sure you read Undead Gods first or you’ll be lost!

Thank you to The Nerd Fam and Caitlyn Batelle for the eARC. All opinions are my own.

[Ashley Cohoon · Rating 4 out of 5]

⭐⭐⭐⭐⭐☆ (4.5/5 stars)

Undead Oaths by Caitlyn Battelle took everything I loved about the first book and turned the volume way up. This is one of those rare middle books that doesn’t feel like filler at all, it feels essential, emotional, and downright addictive.

The story picks up immediately after Undead Gods, throwing Elysia straight into the consequences of the deal she made with Aidan, the god of the dead. There’s no easing into anything here: fate, prophecies, dangerous quests, and a whole lot of emotional fallout hit fast. I loved how the stakes felt heavier this time, not just for the world, but for Elysia herself. She’s still stubborn, anxious, and fiercely determined, but you can feel how much everything is costing her now.

Aidan continues to be an absolute standout. He’s powerful and terrifying when he needs to be, but also quietly devoted in a way that hurts in the best possible way. His love for Elysia is intense, complicated, and full of restraint, which made the slow burn between them even more satisfying. Their chemistry is ridiculous, every glance, every almost-touch, every moment of tension felt loaded. When things finally start to shift between them, it feels earned.

The world-building really expands here too. We get more of the underworld, more of the gods, and more of the mythology that makes this series feel rich and immersive. I also loved seeing the found family elements grow, especially the side characters who bring warmth, humor, and emotional grounding to all the chaos.

What impressed me most is how well this book balances everything. There’s action, romance, character growth, and lore, but nothing feels like it’s crowding out the rest. And that ending? Brutal in the best way. I closed the book already desperate for the next one.

Overall, Undead Oaths is a powerful, emotional, slow-burn fantasy romance that deepens the series in all the right ways. If you love gods, fate, devotion, and a romance that makes you ache before it makes you swoon, this one absolutely delivers

A big thank you to NetGalley and Twelfth House Publishing for an advanced. copy in exchange for an honest review.

[Mercedes · Rating 5 out of 5]

Okay, this is where the series really hooked me!!

After feeling like Undead Gods was very setup-heavy, Undead Oaths comes in with more momentum, more tension, and way more emotional payoff. Everything that was quietly built in book one finally starts to matter here, and it made this one so much easier and more fun to get lost in.

This is also where the Hades and Persephone vibes really show up. If book one was just hinting at that dynamic, book two actually puts it on the page. The slow burn finally starts to burn 🔥 It is still not an over-the-top spice fest, but the yearning, tension, and emotional weight are SO much stronger, and that worked really well for me.

One of the biggest differences for me was how much more alive this book felt. There is more dialogue, more banter, and more actual interaction between characters instead of everything living inside Elysia’s head. The pacing felt tighter, the stakes felt more personal, and I was way more invested in what was happening moment to moment.

I also liked Elysia a lot more in this book. She still made choices that had me going “why would you do that???” but I understood her better here. She feels more active, more decisive, and like she finally has something real to lose. That made it much easier to root for her, even when I did not agree with every decision.

The worldbuilding continues to be a strong point, but it felt more balanced this time. Instead of being overwhelmed with information, I felt like I was watching all the pieces come together. The gods, the politics, the magic, and the consequences of the oaths all started to click.

And yes, Lina the raccoon is still here and still adorable 🦝💛 Every time she showed up, I smiled. As an animal lover, those little moments really grounded the story for me.

Overall, Undead Oaths felt like a big step up from book one. If Undead Gods was about laying the foundation, this is where the series actually starts to shine. I totally get why this is the book that wins people over, and I am genuinely excited and a little nervous to see what happens next!!

❤️ Thank you to Twelfth House Publishing and NetGalley for providing the eARC! All opinions are my own

[Brooke (The_Brookeshelf_) · Rating 5 out of 5]

Elysia Parker made a deal with the God of the Dead but when the fates come into play, what they’ve woven continues to tangle and Elysia has to decide if she can defy the fates or if her world will come crumbling down around her. Undead Oaths is the second book of Caitlyn Battelle’s trilogy, inspired by Hades and Persephone, filled with magic, fantasy, a beautiful God of the Dead, and…puppies? Oh, just you wait!

I am simply blown away by Undead Oaths. This second book of the trilogy surpassed all of my expectations in storytelling, character growth, worldbuilding, dialogue, pacing… really every element I could have ever asked for. The first book, Undead Gods, set the stage for this second book to take off. Undead Gods spent valuable time laying the foundation, allowing this second book to sweep the reader away in a deep dive of adventure with complex characters and realms that were all build with stunning details and layers that they all came to life on the page.

Elysia’s growth throughout this book was an incredible story of pain, heartache, and sacrifice, leading her to find her life’s purpose and meaning. Her journey with each side character, and really with herself,allowed her to take risks like she’s never done before by practicingvulnerability and showing others who she truly is, creating beautiful relationships with each character.

I am so excited to see where Elysia and Aiden’s love story goes because I’m absolutely obsessed with them together. Aiden’s character was so lovable and relatable (the pen obsession and anxiety is very me). I can’t wait for the third book, because let me tell you, Battelle knows how to write a cliffhanger!

Tropes:
🐦‍🔥 Hades and Persephone inspired
🩶 Stubborn, stabby FMC
💀 Possessive death god
🏠 Found family
✨ Magic, Gods, Fates
🖤 My wife and he falls first
♾️ Fated bonds
🔥 Slow burn, yearning, tension
🔒 Forced proximity

A huge thank you to Caitlyn Battelle for allowing me access to both Undead Gods and Undead Oaths through participation on her ARC team. All opinions are my own.

[Lindsey Adams · Rating 4 out of 5]

⭐️⭐️⭐️️⭐️/ ️🌶️🌶️🌶️

What a wonderful retelling of Hades and Persephone! Undead Oaths shines as book 2 in the Undead Gods series. Caitlyn Battelle definitely knows how to balance spice, romance, and drama to create a book that you are unable to put down. Our MCs are well written and the chemistry that moves between them is easy to feel throughout the story.

Book 2 picks up where book 1 ends and Caitlyn immediately reminds readers why this series is worth reading. Continuing the beautiful tension between Elysia and Aidan, Elysia’s deal is now feeling the consequences. When I say slow burn, I mean slow burn. But the pay out when it finally erupts was made all the better by said slow burn. Elysia is fighting to keep her humanity while it slowly slips away, but she never backs down. She stands firm in her beliefs, a rock for those who depend and rely on her, and will defy fate itself to do what she thinks is right.

She compliments Aiden so well, yet is able to stand next to him and rule. Aiden is going to fight for who he wants and he wants Elysia. His vulnerability throughout the story is made so much better after he fully embraces his god of the undead role. Constantly wanting to prove himself to Elysia as the man she can trust and be with completely, while fully embracing what his role means and needs from him.

Caitlyn’s writing pulls you in and keeps you intrigued. The storyline is fresh, although a retelling, pulling you into a world you’ve never experienced before. As twists and turns happen throughout, you will be on the edge of your seat until the very end. Hold on tight though, because the ending will have you needing book 3 as soon as possible. Written with heart and passion you can feel, I highly recommend this series to anyone who is a fan of fantasy and romance.

As always, review any author notes before reading.

What to Expect:
👑Morally Gray Characters
🖤Persephone x Hades Reimagined
👑Possessive MMC
🖤Stubborn FMC
👑Found Family
🖤My Wife
👑Enemies to Lovers to ?
🖤Touch Her and 💀

[Aida Rivero · Rating 5 out of 5]

You guys, I was hooked by Undead Gods, but Undead Oaths? It genuinely consumed my life for two days straight. Caitlyn Battelle knows exactly how to drop you back into the treacherous, atmospheric world of Kava. It's dark, it's dangerous, and the gods are more manipulative than ever—exactly how I like my fantasy!

Elysia Parker is quickly becoming one of my favorite FMCs. She's back, she’s understandably furious, and she is not here for anyone's nonsense. Seeing her struggle with this impossible deal—her life on the line, her sister dying from the "soot," and this intense push-pull with the possessive god of the dead—was just... addictive. Her internal battle between her duty and her undeniably changing feelings for the god was so palpable and real. I felt her tension and frustration! She's headstrong, she's "stabby," and I loved every second of her fighting against a fate determined to break her.

The plot was a total roller coaster ride. There was never a dull moment! The court intrigue, the forbidden magic, and those absolute gut-punching twists kept me up way too late. Seriously, Battelle knows how to deliver a genuine surprise. The world-building remains top-tier—it's immersive and vividly crafted. And that slow-burn romance? The yearning and tension are absolutely exquisite. It's everything you want from a dark Hades and Persephone retelling. Also, can we talk about the side characters? The depth they add is fantastic (and yes, I am emotionally invested in the pint-sized man-eating dog).

If you love morally gray characters, dark romantic fantasy, and heroines who refuse to stay down, you need to read this sequel. Battelle explores betrayal and the painful complexities of love with such emotional depth. And that ending?! I am not okay. I need book three in my hands immediately!

This series has my whole heart. Highly, highly recommend!

10/10 Would recommend to family and friends

[Tiffany Valdez · Rating 5 out of 5]

I received an advance review copy for free, and I am leaving this review voluntarily. I am struggling with words to describe how good this book was.

The world was built even more, I very much liked the unique magic types are tied to the different gods. I also love the gods gambling and hope we see more of it in the future.

There was a lot of character development for a lot of characters. I love the side characters and getting to know more about them. Characters like Grim, Gage, Beatriz, Rollie I loved and want more of.

We definitely got the Hades and Persephone vibes in the second book. Aidan is the absolute best. He is always supportive of Elysia and while he may not tell her everything at first he does it because he cares, or legit can’t. Elysia grows and eventually accepts she deserves love and changes her ways to make better choices. I enjoyed it was realistic that it took Elysia time to adjust and learn she deserves to love and that it wasn’t unrealistically fast.

I enjoyed the different point of views and how it wasn’t the traditional just MMC and FMC views. I liked seeing what was happening with Topp and Rollie. I would have loved to see POV chapters from Aidan, and Beatriz too.

It is definitely a slow burn still by 51% there is barely a foot rub. But there are definitely a few spicy scenes. Absolutely loveddd when Aidan was showing off his golden strands and when he called her his wife!! 😍😍
Elysia stealing Aidan’s pens was adorable and I love Aidan knew but didn’t take them back but just told her not to steal the one he was using.

I am still shocked about a few events throughout the book. I did not see them coming at allll. I can’t wait to see how things turn out!

This book was soooo good. It ended with a lot of things that still need to be resolved but it wasn’t on as major of a cliffhanger as Undead Gods. I am so excited to see what comes next! I am ecstatic I had the opportunity to read this ARC.

[Jessica · Rating 4 out of 5]

This is more of a 4.5 stars than a 4, but alas, Goodreads hasn't listened to my pleas.

Undead Oaths is that rare second book that doesn’t just hold the line, it raises the stakes and sharpens everything that worked in book one. The Hades–and–Persephone–inspired thread finally moves to the center, and the story leans hard into fate versus choice, mortality, and the cost of making deals you didn’t fully understand. Elysia is furious, cornered, and stubborn, especially as the threat to her kingdom and her sister becomes impossible to ignore. The sense of urgency never lets up, and the world feels bigger, darker, and more dangerous with every chapter.

Aiden absolutely steals this book. He’s anxious, guilt-ridden, restrained to a fault… until he isn’t. Battelle does a great job balancing his vulnerability with reminders that he is, in fact, a god of death who can be terrifying when pushed. The tension between him and Elysia is constant and messy and unresolved in the best way. There’s yearning, distrust, attraction, and a lot of emotional friction that keeps their dynamic from feeling easy or safe. I appreciated that the romance doesn’t smooth over the damage or rush emotional trust just because the chemistry is there.

The pacing is fast, sometimes almost too fast, and a few revelations land more casually than expected, but the momentum works in the book’s favor overall. The Fates feel actively antagonistic, the quests carry real consequences, and the supporting cast continues to complicate things in ways that clearly matter long-term. By the end, this no longer feels like a bridge book, it feels like the turning point of the trilogy. I finished it stressed, invested, and immediately wanting the next installment.

Thank you to the author for the ARC. I’ll absolutely be continuing the series.