The Empyrean series has been making waves, especially with the release of "Onyx Storm" earlier this year. All three books are currently topping Amazon's Kindle best sellers list for 2025. The series' popularity surged when "Fourth Wing" was first published in 2023, largely thanks to the influence of Booktok. Since then, this romantasy series has not only captured the hearts of many but also dominated most best seller charts.

The release of "Onyx Storm" has successfully drawn a multitude of new readers to the series, showcasing the viral power of Rebecca Yarros' writing. Her unique blend of fantasy and romance has captivated a wide range of readers. With the recent greenlighting of a "Fourth Wing" TV series at Amazon, the Empyrean series is poised to potentially outshine even the Harry Potter franchise in popularity, provided it continues to play its cards right.

The Physical Editions Are Popular Too

Onyx Storm (Deluxe Limited Edition)

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While the Empyrean series dominates the Kindle charts, it also holds a strong position on Amazon's top selling physical books list for 2025. Both the deluxe and standard editions of "Onyx Storm" are within the top 10, while "Fourth Wing" remains in the top 25.

The only recent challenge to "Onyx Storm's" dominance came with the official release of Suzanne Collins' new Hunger Games book, which briefly pushed it to the second spot on the fiction list. However, with an increasing number of readers discovering the series through "Fourth Wing," there's potential for "Onyx Storm" to reclaim its top position before the end of 2025.

Fourth Wing and Iron Flame are Part of Kindle Unlimited

Kindle Unlimited

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For those eager to dive into the series, the first two books, "Fourth Wing" and "Iron Flame," are available for free on the Kindle app with a Kindle Unlimited subscription. To start your journey with the Empyrean series, simply log into your Kindle account and download these titles before they might no longer be included in your subscription.