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Choice Band

Attack is boosted by 50% but the user is restricted to one move until they switch out.

If the holder of this item uses Sleep Talk, it will select a random move for the first turn, and receive the boost as usual, but all subsequent uses of Sleep Talk or the move chosen by Sleep Talk will fail until the holder switches out.

In Diamond/Pearl, if the holder is brought in from a Pokémon that used U-turn to initiate the switch, and the holder has U-turn, it must use U-turn as its next move. If the holder doesn't have U-turn, it can freely select a move. However; in Platinum, if the holder is brought in from a Pokémon that used U-turn to initiate the switch they can freely select any move, even if the holder has U-turn.

Baton Pass counts as a switch as far as this item is concerned, and thus resets the move into which the holder is locked to no move.

If a Pokémon with a Choice Band is Tricked by / uses Trick on a Pokémon that does not have a Choice item itself, the Pokémon that has the Choice item after the Trick will be free to use whatever move it wants on the next turn only if it went first. That Pokémon will be free to select whichever move it likes regardless of whether it was originally the Pokémon with the Choice item. The Pokémon that moved second will always be locked into whatever move it used on the turn it was Tricked if it is the one holding the Choice item after the Trick. However, if both Pokémon are holding a Choice item, and either Pokémon uses Trick, then both Pokémon will be locked in to whatever move they used on the turn of the Trick(s).

For example, if Choice Band Jirachi is facing Choice Band Bronzong, and Jirachi uses Trick while Bronzong uses Stealth Rock, Jirachi will be stuck using Trick the next turn, and Bronzong will be stuck using Stealth Rock and therefore have virtually no reason to stay in, meaning Jirachi, if it decides to stay in, will have no choice but to Trick the Choice Band onto the incoming Pokémon (unless it has Sticky Hold or Multitype). To expound on this, if the Bronzong user switches in Swampert to the Trick, Jirachi would be free to use whatever it wants. But if it uses Trick again and Swampert stays in to do whatever, then the next turn, Jirachi will be forced to use Trick, and not something like Reflect or U-turn.