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Crater Town (after beating the Gym Leader)

Thief inflicts damage and confiscates the target's held item if the user is item-less. Items taken from wild Pokémon are retained after the battle, while those from Trainer's Pokémon are not. The player's Pokémon's stolen items, regardless of source, are restored post-battle in wi-fi/linked battles. In cases where the item activates on attack (e.g., Focus Band), it does so before being taken, and consumable items like Focus Sash are used and cannot be stolen. Sticky Hold prevents item removal, while certain items, like the Griseous Orb on Giratina or Mega Stones on respective Pokémon, are unremovable.