Rebecca Yarros's short story collection, Threshing Day, is basically filler that's targeted straight at hardcore Fourth Wing fans. But that's precisely why they'll love it.
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Yes, Rebecca Yarros' 'Threshing Day' Is Complete Filler (But It's Fun)
This slim collection of tales is as ephemeral as dragon smoke, but it's still fun getting to know some of the Fourth Wing secondary cast a bit better.