Sundered Rock was where the final battle of the War Of The Prisms took place. There, Gavin and Dazen Guile faced off in one-on-one combat, and Dazen defeated his brother, but chose to spare his life and assumed his brother's identity, feeling that those who allied with Gavin were far better prospects to govern the Satrapies than his own allies, who were mostly mercenaries, psychopaths, and disreputable folk of every sort.