Opening Section

Admiral Chamrajnagar berates Graff for taking so long to bring Ender to Eros. The war is approaching quickly, and every moment of preparation is precious. As Graff and Chamrajnagar talk, Graff reveals that he owns nothing and cares for little except his students.

Main Narrative

Ender hates Eros, a small asteroid full of tunnels, which all seem to be the wrong size. Many other students live on Eros, but the teachers keep Ender totally isolated. Ender does not complain; he knows it will do no good.

For a year, Ender is drilled on a game called the simulator, “the most perfect videogame he had ever played.” The simulator reacts to Ender’s every strategy, and Ender enjoys meeting new challenges as the teachers add more and more complex wrinkles into the game. Soon he is deftly speaking commands into a microphone and manipulating many fighters at once.

One day Ender gets a new teacher, Mazer Rakham, the military leader responsible for defeating the buggers in the last invasion. Mazer explains that he won by killing the bugger queen that was leading the invasion. When she died, the rest of the bugger army died on its own. They were like many separate parts of one body, unable to live without their guiding mind.

Buggers are smart; Mazer believes the remaining buggers will have learned to keep their queens out of harm’s way. That means Ender will need a different strategy. To Ender’s advantage, he has a new weapon, called Dr. Device, which sets off a chain reaction to destroy everything around it. Also, Ender’s officers and soldiers will be intelligent individuals, unlike their bugger counterparts. A fight between humans and buggers is a fight of many minds against only one.

When Ender goes to his next session on the simulator, he learns that he has a new set of squadron leaders to command. They are Petra, Bean, Dink, and many of Ender’s other friends from Battle School. Although the squadron leaders are now on Eros, Ender is kept separate from them. He works with them through the simulator but never sees them face to face. Nevertheless, they work hard together, and soon the ships on their screens fly together as well as a bugger fleet but with more individual independence.

One day Mazer tells Ender that he is starting simulations of real battles with bugger forces. Ender and his friends win the first fight easily because, as Mazer explains, the simulated buggers do not know how Dr. Device works.

Ender and his squadron leaders fight another battle every two or three days and practice constantly between battles. The challenges grow more and more difficult. Ender suppresses his fatigue and loneliness and immerses himself totally in the game. Even so, the stress takes a toll. Ender has nightmares about the buggers and about Bonzo and Stilson.

Ender continues to win, but by increasingly narrow margins. One day during a battle he pushes Petra so hard that she fails to do her job. Petra is humiliated, and Ender knows he can never put so much pressure on her again. He begins rotating his squadron leaders in and out of battles, giving each of them time to rest. Ender gets virtually no rest.

Ender’s nightmares grow worse, and he begins to wonder if the strain might kill him. One day during a practice, he passes out at his controls. When he wakes up, he fights and wins another battle, but he is so tired he goes to bed early. In his sleep, he thinks he hears Colonel Graff and Mazer Rakham saying they love him. He dismisses this as a crazy dream. The teachers are his enemies. They have no compassion.

When Ender awakes, he goes to the control room to find it full of people. Mazer explains that Ender is about to take his final examination at Command School. To graduate, he must win one last simulated battle.

The battle is waged around a planet, where Ender’s ships are outnumbered a thousand to one. The arrangement is so unfair that even the adults in the room seem upset by it. Ender’s squadron leaders are appalled.

Inwardly, Ender rages against the teachers for creating such an unfair game. He decides to win this battle in a way that will make the teachers as angry as he is. He moves his fighters through the chaos of defenders, sacrificing most of his ships to do so. Then he uses Dr. Device to blow up the whole planet.

When Ender is finished, the room erupts into cheers. Mazer explains that Ender was not really playing against a simulator; he was fighting the actual buggers. He has just destroyed the buggers’ home world, and humanity has finally won.

Ender is devastated. He feels guilty for causing so much death, even though he did not know what he was doing. He not only led those on his manned spacecrafts to their deaths but killed the entire bugger species. Graff and Mazer explain that humanity could not win unless their commander had so much empathy that he would understand how buggers worked. Nobody with that much empathy would want to kill off a whole species, so the teachers believed that their only choice was to trick a talented child into doing both at once.

Now that the bugger threat is gone, a land war is erupting on Earth. Ender is still a tool, and many leaders want to kill him so that other leaders cannot use him for a tactical advantage. The teachers want Ender to flee, but he refuses. When Eros is attacked, his squadron leaders come to see him. As the adults fight and eventually win, Ender tells his friends he never wants to command anyone again.