Shadow of the Hegemon

This is a picture from Orson Scott Cards's Ender's game series, specifically Shadow of the Hegemon. The character's are presented as followed:

Top left: Peter Wiggen
Bottom left: Bean
Top right: Achilles
Bottom right: Petra

In the background is the colony ship where Ender and Valentine are sent away from earth, leaving the fate of the earth to the rest of the children from battle school to rebuild and control a new world...