The Pokémon Summer Camp competition is heating up with Ash & Tierno's teams having the exact same amount of points. The next challenge is PokéEnteering, where each team has to go to various locations and collect stamps, and the fastest time wins. Both teams go smoothly through the challenge, but soon a mysterious mist appears and Bonnie gets lost. To top it off, she sees the legendary Pokémon, Xerneas. Will Ash, Tierno & co. manage to find Bonnie and still win the competition?