The assault by Roland's ka-tet on the Devar-Toi, the Breaker prison in Thunderclap. With the help of rebel Breakers including Ted Brautigan and Dinky Earnshaw, Roland's group attacked the facility to stop the systematic destruction of the Beams. During the battle they slaughtered most of the can-toi, taheen, and human guards but spared the Breakers themselves, telling them to make their way to the Callas and beg the folken's forgiveness. The battle came at a tremendous cost to Roland's ka-tet.