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Book Review — Series Sequel

Iron Flame

Rebecca YarrosFantasy RomanceThe Empyrean #2 2023 • 623 pages~12 min read
Iron Flame cover
Our Rating
★★★★½
Best For
Everyone who finished Fourth Wing — you are reading this regardless of what this review says
Content Note
Explicit romance, war violence, significant character deaths, emotionally demanding
"Violet knows the truth about the Venin. The war is real. Xaden has been keeping secrets. And the world outside Basgiath is about to become impossible to protect everyone inside it from."
Read Fourth Wing first. Iron Flame picks up directly from the end of Book 1. This review contains unavoidable Fourth Wing spoilers in its basic description — if you haven't read Book 1, start there.

What This Book Is About

Iron Flame opens in the immediate aftermath of Fourth Wing's ending — Violet processing the full scope of what Xaden has been hiding, the newly confirmed reality of the Venin threat, and the question of whether the love she has for someone who withheld this much is still the same love. Yarros does not give her an easy answer, which is exactly right.

The book is bigger than its predecessor in almost every dimension. The world expands — we see more of Navarre, the other kingdoms, the political landscape that the war with Venin has deformed. The cast grows. The stakes escalate. The romance is tested in ways that go deeper than the first book's obstacles because the obstacles are now internal: two people who love each other, both of whom have reasons to withhold, both of whom are carrying things that would break the relationship if they allowed themselves to put them down.

Violet's signet power — her ability to weave lightning — develops in ways that complicate her sense of herself and her relationships with her dragons. The magic system deepens. The war escalates. And several characters who were background figures in Book 1 become central in ways that make the world feel genuinely expanded rather than just busier.

At 623 pages, Iron Flame is longer than Fourth Wing and is paced differently — more politically complex, slower to certain emotional payoffs, with a harder middle section that some readers find testing. Those who push through find that the emotional stakes by the final act are considerably higher than anything in Book 1, and the ending sets up Onyx Storm with a brutality that is entirely earned.

Who Should Read This

If you read Fourth Wing, you're reading this. That's not snark — the cliffhanger ending of Book 1 makes this book essentially mandatory for anyone who finished it. But for context:

What Makes It Special

The Violet/Xaden dynamic in Iron Flame is the best version of their relationship across the series so far, paradoxically, because it's the most damaged. A relationship that's been constructed on withheld information has to be rebuilt on different terms, and watching two people who are clearly right for each other figure out how to do that — while also fighting a war and training an army — is both emotionally rich and structurally interesting.

Yarros expands the secondary cast with real success. Several characters who were interesting but peripheral in Book 1 become load-bearing in Book 2. The political complexity around Navarre's war effort — who knows what, who is complicit in the lies, what it costs to tell the truth in a hierarchy that depends on enforced ignorance — adds a layer to the story that gives it more weight than pure romance-with-dragons.

The magic system deepens in ways that feel earned. Violet's power and what it does to her, the escalating threat from the Venin, the specific mechanics of how signet powers work and can be used against their wielders — all of this is developed with the same careful construction as the first book, and it pays off in the final act in ways that recontextualize the early sections.

The Good & The Honest

What works:

What to know:

⚠️ Spoiler Zone — Major Deaths and Reveals Discussed Here

Liam's death was the emotional gut-punch of Book 1. Iron Flame delivers comparable blows. The deaths of beloved characters in the latter half of the book — several of whom the reader has been with across two books now — are handled with the same earned devastation as Liam's. Yarros does not kill characters for shock value; she kills them because the story requires it and because she's made the reader care enough that it costs something.

The reveal about Violet's signet power — specifically the scope of what she's capable of and what it might mean for the Venin war — is the book's most significant plot development. It reframes her position within the narrative from "important rider" to "potentially war-determining figure," which has implications both for the romance (Xaden's protectiveness becomes more complicated when the thing he's protecting is also the thing that needs to be in danger) and for the series' endgame.

The ending — Xaden's transformation, which I'll leave undescribed for readers who haven't finished — is the series' most significant plot development and the reason everyone reading Book 2 needs Onyx Storm immediately. It changes the shape of the central relationship in ways that are either the most interesting thing Yarros has done with it or the most painful, depending on where the next book goes. The reader's willingness to trust her at this point is a function of how much Book 1 and Book 2 have earned that trust. She has earned it.

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The Verdict: Essential If You Read Fourth Wing — Have Onyx Storm Ready

Iron Flame is a bigger, harder, more emotionally demanding book than its predecessor and rewards readers who give it the time it needs. The ending makes Onyx Storm non-optional. Plan accordingly.

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