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Causes the target to repeat the move it last used for 4-8 turns, with a 20% chance to last each length. If the target's move can target more than one of its opponents, the target will be chosen at random. If the target runs out of PP while Encored, the Encore will end regardless of how many turns it has been running for. If the target could not legally select the affected move, it will be forced to select Struggle. If a Pokemon which is switched in via Baton Pass also knows Baton Pass, it will be forced to select Baton Pass as its next attack if it is targeted by Encore before using another move. Similarly, if a Pokemon is switched in via U-turn and then targeted by Encore, it will be forced to use U-turn if it knows that move.
Encore will fail if the target has not selected a move since switching in; if the target tried and failed to use a move this turn (due to sleep, paralysis, recharging, etc) before being targeted with Encore; if the affected move is Transform, Mimic, Sketch, Mirror Move, Encore, or Struggle; if the target does not know the affected move; or if the affected move has zero PP remaining.