Walkthrough: After defeating Kahuna Hala in your Grand Trial, your Island Challenge, as far as Melemele Island is concerned, has been completed. Whether you decide to check out Ten Carat Hill or not, eventually make your way back to Big Wave Beach. For the first time, you will get to experience Mantine Surf. Not only will you earn points that will be converted into credits you can use with Move Tutors as you play Mantine Surf, but you will also travel to the next island of The Alola Region, Akala Island, as you do. You will land on the beach of Heahea City, thus continuing your Island Challenge.