SS Son Goku, Stockpiled Power (Ultra-Bout Series Tournament Pack Vol.2) (P-733) - Tournament Promotion Cards

[Auto] If your Leader’s back side is "SS Son Goku, Fearless Fighter" : When this card is played, during this turn, when you would play a Unison with "Empower" from your hand, reduce the specified cost by Y.
[Activate:Main] [Limit 1] Y, if you have 2 or more energy : Draw 1 card and play this card from your hand.
[Activate:Battle] [Once per turn] Choose up to 1 of your yellow Unisons and it gets +15000 power for the battle.