"Killing your battery" in this context doesn't mean your iDevice dies while you're afking. It means that your battery will die faster. The more you afk on online games, such as this one, your battery will die faster when it's not plugged in. For example, I've afked before with my iPod. I did it so much, that now my iPod has to be plugged in, charging, almost at all times... Although, I never really use my iPod anymore. I'm a lot more careful about my iPad. I don't want my 500 dollars wasted because of a game...