"Right behind you," Rainbow said, and meant it. She'd just had to kill a pony, but she did it to save Lightning. She realised that maybe she'd been thinking about this all wrong. She thought that to kill a pony you had to enjoy it on some fundamental level, which she knew was probably wrong to begin with, and a horrible thing to think about Twilight, but couldn't see another reason why. She never thought that you did it to save yourself, or your fellow soldiers, or your loved ones back home, or because sometimes you simply had to. It wasn't all about the killing at all, but could be about saving those that pony might hurt later. It was still a bitter pill to swallow, but she felt it was one she could swallow again and again if she had to.