Perish Song

Every Pokémon is given a counter that starts at 3 and decreases by 1 at the end of every turn, including this one. When a Pokémon’s counter reaches zero, that Pokémon faints. A Pokémon that leaves the field will lose its counter; its replacement does not inherit the effect, and other Pokémon’s counters remain. This effect is passed on by Baton Pass. This move cannot be copied by Mirror Move.