Sleep Talk is a status-affecting Normal-type move. It is TM82, and can be found in Vinoville Town left of the house west of the berry field.
Sleep Talk can only be used while the user is asleep and will fail if the user is not. Sleep Talk randomly chooses one of the user's moves other than Sleep Talk itself and uses it. PP will be deducted from Sleep Talk only, which means that it can be used to execute moves that have no PP left. Because Sleep Talk has normal move priority, a move with higher or lower priority may not be executed when it normally would. For instance, Sleep Talk may cause Quick Attack to be used after a normal priority move or Roar to be used before a normal priority move. If Sleep Talk calls Metronome or Mirror Move and thus in turn calls a two-turn move, the move will fail.
Sleep Talk will not select itself, any move currently disabled, or any of the unselectable moves listed below.