how does ender control the situation so he only has to fight one?

Ender sleeps and wakes that evening to notice that his army is to battle Griffin and Tiger Armies simultaneously. Ender is physically and mentally exhausted, and does not want to fight, but when Ender tells his army, they are excited. In the battleroom, there is a cube of four "stars" directly in front of Ender's gate, so he cannot see the enemy. For reconnaisance, he sends Bean around with the thin wire. After the report, Ender decides to throw them off by using a formation instead of their normal fluid attack. The formation distracts the armies, leaving open a path to victory at the enemy gate. Dragon soldiers perform the closing "victory" maneuver and win on that technicality. Anderson then changes the rules to prevent such a "win" from happening again. Ender and many of the soldiers complain to Anderson about the recent unfairness of the battles. That night, when Crazy Tom asks about practicing, Ender replies that they will never practice again, because he does not "care about the game anymore! ... The game is over."