: Since his castles are famously poorly built and unproductive , any of his buildings that are destroyed have a 25% chance to collapse into "Debris Piles" that act as rough terrain, slowing down invading forces. Why This Works
This trait would trigger when The Rat's castle walls are breached or his health drops below a certain threshold.
Born as an illegitimate child to the wealthy De Puce family, the Rat grew up in obscurity. His mother, a former serving wench for the Duke, was granted some financial ease, allowing him to grow up without the typical hardships of the poor, yet he remained embittered by his fractured family.
(Memoirs of the Duke of Flea, peer of the blanket)