Threshing Day may be the first book I have watched cause a fandom argument before most people even understood what the book was. Impressive, really, if you think about it.
The important bit now is that Rebecca Yarros’s Threshing Day released September 29, 2026. It is a collection of thirteen Empyrean stories built around riders and the dragons who chose them and? It is Empyrean 3.5. It is not book 4 and it does not resolve the Onyx Storm ending. (Which frankly…what was that? I’m still in shock and need to know. I have all the gossip on book 4 here.)
UPDATE: AND I WAS RIGHT.
When I wrote this before release, I said I’d bet my hat there were going to be clues sprinkled through these stories. There are. A lot of them.
Some of these stories reframe character motives, and there are details you can absolutely miss if you aren’t paying attention to the larger Empyrean puzzle. I was screaming, “Wait, WHAT?” at my book more than once.
I’ve pulled all of those moments into a separate spoiler-controlled Threshing Day theory guide so you can follow along story by story without ruining the ones you haven’t read yet.
The short version
- Released: September 29, 2026.
- Format: thirteen stories about Empyrean characters and their dragons.
- Series position: Empyrean 3.5 / companion collection.
- Length: about 224 pages.
- POVs: Brennan, Mira, Xaden, Garrick, Dain, Bodhi, Imogen, Rhiannon, Sawyer, Ridoc, Liam, Sloane and Aaric.
- Deluxe first edition: sixteen full-colour illustrations by Joe Requeza.
- Spice: none.
- Required before book 4? No. Worth reading if you theory-craft? Absolutely.
What is Threshing Day actually about?
Threshing is the Basgiath trial where first-year cadets try to bond with a dragon. ‘Try’ is the word of the day here because the dragons choose really, at the end of the day.
Threshing Day gives us thirteen of those bondings from characters we already know: Brennan, Mira, Xaden, Garrick, Dain, Bodhi, Imogen, Rhiannon, Sawyer, Ridoc, Liam, Sloane and Aaric.
What surprised me most is how much some of these stories change the way I look at characters we already know. There are motives that make more sense now and some that will shock you. If you are really into theory crafting, these are the details you do not want to skim. Grab a notebook or scribble in the margins.
Where can you buy Threshing Day?
Why is Threshing Day not Fourth Wing book 4?
Because it looks backward, while book 4 has to move forward from Onyx Storm. Essentially, it’s a collection of short stories.
The retailer placeholder made this much messier than it needed to be, and everyone snooping didn’t help (cough, I totally wasn’t part of the problem). ‘Untitled Empyrean (Not Book Four)’ appeared for months, and was found in seconds. Which is hilarious. People assumed what we knew (book 4 was coming) would still be true. And it simply wasn’t it.
Book 4 remains the mainline sequel and the penultimate book in the planned five-book series. Threshing Day is a companion collection.
Which Threshing Day edition should you buy?
If you care about the art as much as the stories, the deluxe first edition is the one to get. It has sixteen full-colour illustrations by Joe Requeza, and after reading it I’m glad I went physical because the art is part of the fun.
If you are here for the text, the ebook or audiobook will do the job perfectly well. But if you are a note-taking, tab-sticking little goblin like me, the physical copy is extremely easy to turn into evidence.
Deluxe stock can vary by retailer and country, so check the actual edition details before buying if the illustrations are the reason you want it.
What is the spoiler-free verdict on the thirteen stories?
They are short, but not empty. The best ones work because they focus tightly on one emotional decision: who this rider was before the dragon chose them, what the dragon saw, and what little piece of the future was already sitting there.
This is absolutely a puzzle-piece book though. If you read it only for cute bonding scenes, you’ll get those. If you read it with your conspiracy-board glasses on, there is much more happening underneath.
Who are the thirteen Threshing Day POV characters?
The thirteen POVs are Brennan, Mira, Xaden, Garrick, Dain, Bodhi, Imogen, Rhiannon, Sawyer, Ridoc, Liam, Sloane and Aaric.
And yes, Liam hurts. But weirdly, it wasn’t Liam’s story that got me to shed a tear. It was Sloane.
Does Threshing Day actually earn its place in the series?
Companion books get side-eyed because readers get charged hardcover money for deleted scenes that should have been part of the story to begin with, and feel scammed. I think this is the perfect timing for this drop though, because it should give us extra clues for the rest of the story, as well as pull on heart strings. If this came out after book 5, then we might feel more cheated.
The great thing about these stories as well, as they are not simply a new POV/same scene scenario.
The risk is that explanations can shrink mystery. Sometimes it’s the gaps in the stories that our mind fills which make us feel personally connected to characters. For instance, Xaden and Sgaeyl’s bond has power partly because we do not know every inch of it and imagine it to be like Violets but with our own brain version of Xaden’s charm. Yarros is a good writer, and has probably considered all of these things and much more.
If you’re the kind of reader who loves all the clues, start with my Threshing Day theory guide. Then head to the Fourth Wing Book 4 tracker, The Wildest Empyrean Theories, or Onyx Storm Theories That Might Actually Be True.
Can you still get the illustrated deluxe edition?
Possibly, depending on stock. If the sixteen illustrations are the reason you want the book, check the retailer listing carefully because standard and deluxe copies are not the same thing. I would also check indies before paying silly resale prices.
Is there spice in Threshing Day?
No. There is no spice in Threshing Day. This is a dragon-bonding and character-history book.
You still have Basgiath, violence, injuries, death and the general problem of teenagers being dropped into a lethal military school, but there are no explicit sex scenes.
Why Threshing is strong enough to carry a whole collection
Threshing has a lot of lore to spill. The whole rider system depends on dragons choosing humans, while the humans build an entire brutal institution around pretending they can prepare for that choice, when at the end of the day, it’s all dragons and we’re not entirely sure why they chose who they do. This book might open that up and explore it.
Every short story can ask the same question – what did the dragon see? – and give us a completely different answer than what we might expect from the kind of human environment we have been watching. It might even be surprising. Maybe the dragons don’t act in a way we have even considered yet.
Should you read Threshing Day before book 4?
You do not need Threshing Day to understand the main plot. I would be very surprised if Book 4 expects every reader to have completed a 3.5 companion collection first.
Required for those of us with notes, theories, and increasingly deranged opinions about dragons? I would not skip it.
Where this leaves us
With thirteen bondings, a pile of new character context, and enough foreshadowing to make my notes app look unwell.
And yes, I did cry about Liam. But weirdly, it wasn’t Liam’s story that got me to shed a tear. It was Sloane.
Mostly, though, I finished this book and ran straight to my keyboard to start tracking notes. If you did the same, the full Threshing Day theory guide is here. You can also keep up with the Fourth Wing Book 4 tracker, or head to the romantasy hub when you need something else to read while we wait.
Frequently asked questions
Threshing Day was published September 29, 2026.
No. It is an Empyrean companion collection positioned between the mainline novels. Book 4 is a separate sequel to Onyx Storm.
The book contains thirteen stories about Empyrean characters and their dragons, focused on the day those rider-dragon bonds formed.
Yes. Xaden and Sgaeyl are confirmed to be included.
The deluxe first edition includes sixteen full-colour illustrations by Joe Requeza and is planned as a limited North American first edition while supplies last.
No, according to Yarros. She has described the collection as a return to Basgiath while she continues work on book 4.
