Whether it be getting promoted earlier than others, having to fight various battles a day, etc. He manages to prevail every time. Ender realizes early on that he will have to hurt his enemies before they even get the chance to touch him, but he doesn't stop there. He makes sure they won't bother him again. This leads to him questioning his actions and comparing himself to the ruthlessness of Peter. He speaks of this with Valentine. "No, you don't understand. I destroy them. I make it impossible for them to ever hurt me again. I grind them and grind them until they don't exist.".
The manipulativeness and unfairness of the adults at the military is also an obstacle Ender adapts to and conquers. “I don't care if I pass your test, I don't care if I follow your rules. If you can cheat, so can I. I won't let you beat me unfairly - I'll beat you unfairly first.”. After having enough of his team being unfairly treated and constantly thrown into battles with disadvantages, in a battle he directs his team to go for the gate even though the opponents were still