Rebecca Yarros has announced the fourth addition to the mega-bestselling Empyrean series on Instagram. The book is titled Threshing Day and will be available on September 29th this year.

Threshing Day is a little different from the other books in the series, though. It is not a sequel to the third book, Onyx Storm. Instead, it is a collection of 13 stories that follow various characters on Threshing Day—an important event in the series when Basgiath War College cadets first bond with their dragons for life. The deluxe first edition also features 16 original full-color pieces of art by Joe Requeza.

In the same announcement, Yarros mentioned that she is still at work on book four.

Threshing Day, however, is available for preorder now.

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