Metronome on multiturn attacks?

Question

For instance, if I put a metronome on my garchomp and it uses outrage, it only takes 1 pp for three turns of damage. Would metronome double the power every turn or every time I click the move and it uses a pp? Moves like outrage, uproar, razor wind, etc

Answer 1

Similar question here;
http://pokemondb.net/pokebase/131254/does-metronome-item-work-for-outrage

You have to decrease by a PP for it to have an effect. Metronome is a really useless item anyway =/ unless you're attempting a max damage shuckle!