Hau is a friendly rival in Pokémon Sun and Moon, introduced early in the game after the player receives the Sparkling Stone. He battles the player multiple times during the island challenge, receives a Z-Ring from Kahuna Hala, and participates in events at the Pokémon Research Lab. In the post-game, after completing trials, Hau challenges the player as the final opponent before becoming Alola Champion following victory over the Elite Four. He also gives Z-Crystals and interacts closely with characters like Selene, Lillie, and Professor Kukui.