The player starts off moving from Kanto to Alola's Melemele Island with their mother. After meeting Lillie and rescuing her special Pokémon she calls Nebby, the player obtains a starter Pokémon from local Professor Kukui and embarks on the island challenge, a coming-of-age custom spanning trials across Alola, along with local youngster Hau. Unlike in previous games, trials involve battles with powered-up Pokémon, followed by battles with each island's Kahuna upon completion of an island's trials. Throughout this, the player encounters Team Skull, a gang of people who quit the island trials whose members include their leader Guzma, and enforcer Gladion. The player also encounters the Aether Foundation, an organization aiming to shelter Pokémon from various threats.
The player controls a young trainer who goes on a quest to catch and train creatures known as Pokémon, and win battles against other trainers. By defeating opposing Pokémon in turn-based battles, the player's Pokémon gains experience, allowing them to level up and increase their battle statistics, learn new battle techniques, and in some cases, evolve into more powerful Pokémon. Players can capture wild Pokémon, found during random encounters, by weakening them in battle and catching them with Poké Balls, allowing them to be added to their party. Players are also able to battle and trade Pokémon with other human players using the Nintendo 3DS' connectivity features. As with previous games in the series, certain Pokémon are only obtainable in either Sun or Moon, with players encouraged to trade with others in order to obtain all Pokémon from both versions.
Source: Wikipedia, "Pokémon Sun and Moon", available under the CC-BY-SA License.
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