Quick recap
Decades after humanity nearly lost Earth to the Formics, it's training children for war. Colonel Graff picks 12-year-old Ender Wiggin and takes him to Battle School in orbit. Kept isolated on purpose, Ender gets help from Petra, draws Bonzo's hatred and ends up commanding Dragon Army, a squad of rejects that starts winning everything. After a fight that leaves Bonzo badly hurt, Ender wants out but comes back. At a forward base, Mazer Rackham runs the final test, a simulation where Ender sacrifices most of the fleet to destroy the Formic home world. It wasn't a simulation. Devastated, Ender finds the last queen, who gives him an egg. He heads into space to find her a new home.