Battle of Castle Greyreach

The Battle of Castle Greyreach was the final battle in the Blackshade Civil War, where the fighting ended up leading to Empress Ianthe Pyredane's personal bastion. The Rebellion made use of a devastating new weapon, the plague bomb, and were able to kill every living Imperial there, including the Empress.

After this crippling battle, the Empire was forced to stand down and arrange a peace treaty with the rebels, which served as the foundation of the Republic.