What is the importance of Sun Rock in the novel, Fevered Star?

Sun Rock is where the massacre of the Watchers took place just before the events of Fevered Star. It is referenced by many others. This includes the Odohaa who see it as a symbol of divine vengeance. Ultimately, Naranpa and Serapio meet and fight on Sun Rock. Then, she encourages to unite the rest of Tova before leaving the city herself.