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Poké Balls are important items originating from the Pokémon series; their purpose is to store and mobilize Pokémon within the ball when they're not in battle. They have appeared in all four installments of the Super Smash Bros. series as items, and serve as the Pokémon series emblem. When thrown, the Poké Ball will release a random Pokémon out of the ball, say its cry, and attack. In Super Smash Bros. Brawl, the Pokémon Trainer uses a Poké Ball to change between his three different Pokémon: Charizard, Squirtle and Ivysaur.
In Super Smash Bros. for Nintendo 3DS / Wii U, the Master Ball variant of Poké Ball appears as an item. They specifically release only rare and Legendary Pokémon, while the regular Poké Ball can release any Pokémon.
For a complete listing of Pokémon coming out of Poké Balls, see the Pokémon article.
Super Smash Bros. Melee
Super Smash Bros. Brawl
Super Smash Bros. for Nintendo 3DS / Wii U