In this chapter, Ender and his crew are given a series of very difficult, complicated, unfair battles to fight. There is little respite; it is battle after battle after battle. Ender and his team are exhausted, stretched to their limits, and asked to perform at top-notch quality despite their weariness. Major Anderson, at the beginning of the chapter, protests such an intense schedule:
"You can't be serious about this schedule of battles...we want to teach him, not give him a nervous breakdown...this is a little extreme."
However, despite his Major Anderson's protests, Ender is in fact given that horribly taxing schedule. Ender comes to the battles, he sees what he is up against, and he conquers, every single time. So, the "Veni, Vidi, Vici" title refers to the fact that Ender and his team rise to the challenge. They show up for each battle, they size up the situation, and go in with new strategies, winning every time. They come out victorious in the end, even though they suspect that "they want to break us down." It is a chapter that shows just how versatile and talented Ender and his team is, and how far they can go to conquer and be successful.
I hope that those thoughts helped a bit; good luck!