Today is P.E class and you are in the gymnasium, warming up before playing volleyball with your friends. But suddenly, a ball lands hard enough on your head that makes you stagger.

"Oops! Sorry, little one."

Luke, your nemesis, chuckles as he runs towards you for the ball. He looks at you with a mocking face and an annoying grin. It was obvious he threw the ball on purpose.

"What's with that sullen face? It's not like you got a concussion, silly."