What Is the Threshing?

The Threshing is the dragon-bonding trial in Rebecca Yarros's Empyrean series (Fourth Wing, Iron Flame, and Onyx Storm). It is the day when first-year cadets at Basgiath War College walk into the Vale — the dragons' territory — and the dragons themselves decide which cadets are worth bonding. Cadets do not choose dragons. Dragons choose riders, and they are famously unforgiving about it.

Why is it called a “threshing”?

The name is an agricultural metaphor: threshing is the process of separating grain from the chaff. On Threshing Day, the dragon flight separates those who will become dragon riders from those who will not. In the books the separation can be literal and lethal — cadets who are not chosen are cast out of the Riders Quadrant, and the Vale itself is dangerous ground.

What actually happens on Threshing Day?

• Cadets enter the Vale on foot, in front of the assembled dragon flight. There is no scheduled order — dragons pick their moments.
• A dragon evaluates a candidate and either bonds with them or does not. In the books, a bond is announced when a dragon clocks a cadet and claims them.
• Cadets who survive the day unbonded lose their place in the quadrant. This is why the Threshing is equal parts ceremony and ordeal.

What is Threshing Day in the books vs the games?

In canon, Threshing Day is a single event inside a much larger story — it is where riders like Violet Sorrengail bond dragons like Tairn and Andarna. The phrase has since become shorthand in the fandom for “which dragon would choose me,” which is exactly the question our games play with.

This site runs two fan-made takes on the idea. The Threshing Day game is the full valley trial — a sequence of high-stakes choices that can end in a bond or a burn. The dragon quiz is the fast version: six dilemmas, about two minutes, one dragon result. Both are unofficial, free, and need no account.

Is the Threshing real canon or fan-made?

The Threshing itself is canon to the Empyrean book series. Everything on this site — the 30 dragon breeds, the color and tail system, the battle simulator, the tier list — is our own fan-made creation built around that concept. We are not affiliated with Rebecca Yarros, Entangled Publishing, or Red Tower Books, and we clearly mark which parts of the site are original game systems rather than book lore.