Have you ever seen the yellow lightnings that your Boonies can get when challenging other Boonies? They allow you to use one of your special skills. The more yellow lightnings you get, the stronger the special skill you are allowed to use on your opponent.
With enough yellow lightnings, you can defeat the other Boonie using your tribal attack skills. You choose them at the bottom of the screen:
If you want to defeat the other Boonie using a neutral attack skill, choose the cookie:
That can make them lose a lot of energy at once. But don’t forget that your opponents have special skills too. Be smart and look for the best moment to use your special skills and win the challenge.