What do the games mean to Ender and the book?
The overriding metaphor of “game” is a series of competitive encounters regulated by rules of engagement. In this book, the “games” begin with the torturing and threatening of Peter on his two siblings: “You be the buggers.” The next “game” is the violent encounter of Ender and the bully, Stilson, in which Ender “breaks the rule” of the “game” by being over-violent. His explanation, that he wanted to show Stilson’s buddies what would happen to them, and therefore prevent further violence, is a small design that imitates the larger design of Ender’s approach to all “games”—he will challenge the rules of the “games” he is forced to play, thereby altering the results. The games in military training camp, for example, are won by Ender and his teams because Ender changes the expectations, changes the limits of the games; this is also what he does to the “game” of following the “rules” of his trainers. The final “game” of battle with the Buggers, “Ender’s game”, is to change the rule “We must hate the Buggers” to “We should preserve the Bugger culture”—his implanting the Bugger colony on another planet. So in the final analysis, Card is suggesting that humans might mitigate violence on Earth by making a new “game” of national/cultural understanding: “Card’s game”.