Pokémon Sleep is adding Mewtwo as a new Special Pokémon on Sept. 14, 2026, at 3 p.m. Players will be able to encounter the Psychic-type Pokémon during sleep research at Greengrass Isle, Greengrass Isle (Expert) and Cyan Beach (Expert), where Mewtwo will have a Snoozing Sleep Type. Its main skill, Psystrike (Berry Zone), increases Snorlax’s Strength while creating a Berry Zone that boosts the Strength gained from Mago Berries. The Berry Zone’s effects can stack each time the skill activates and remain active until players move to another research site. As a Special Pokémon, only one Mewtwo can be on a team at a time.
Source: Official Pokémon Sleep news
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