Okay kiddo, I'll explain what double rush means. So imagine you're playing a game with your friends where you all have to run from one end of the playground to the other. When you start running, you notice that someone else is running too and they're trying to get to the same spot as you. That's called a rush, because you're both rushing to get there first.
Now, double rush means that there are two people rushing towards the same spot at the same time. It's like a race with two people instead of one. You both want to get there first, but there can only be one winner.
So you might have to use some special skills or tricks to get ahead of the other person. Maybe you're really fast and you can run faster than the other person. Or maybe you're really good at dodging obstacles, so you can get past them quicker.
But remember, it's just a game and everyone should have fun, even if they don't win. So even if you don't get to the end first, you can still be proud of yourself for trying your best.