Ender's Game

And for pleasure, there was the simulator, the most perfect videogame he had ever played. Teachers and students trained him, step by step, in its use. At first, not knowing the awesome power of the game, he had played only at the tactical level, controlling a single fighter in continuous maneuvers to find and destroy an enemy. The computer-controlled enemy was devious and powerful, and whenever Ender tried a tactic he found the computer using it against him within minutes.

I am your enemy, the first one you’ve ever had who was smarter than you. There is no teacher but the enemy. No one but the enemy will tell you what the enemy is going to do.

Ender, for the past few months you have been the battle commander of our fleets. This was the Third Invasion. There were no games, the battles were real, and the only enemy you fought was the buggers. You won every battle, and today you finally fought them at their home world, where the queen was, all the queens from all their colonies, they all were there and you destroyed them completely. They’ll never attack us again. You did it. You.