Brandon Sanderson: Cytonic (Skyward, Book 3)

Description

She proved herself one of the best starfighters in the human enclave of Detritus and she saved her people from extermination at the hands of the Krell - the enigmatic alien species that has been holding them captive for decades. What's more, she travelled light-years from home as a spy to infiltrate the Superiority, where she learned of the galaxy beyond her small, desolate planet home. Now, the Superiority - the governing galactic alliance bent on dominating all human life - has started a galaxy-wide war. And Spensa has seen the weapons they plan to use to end it: the Delvers. Ancient, mysterious alien forces that can wipe out entire planetary systems in an instant.