When the control of this face-up card on the field shifts to your opponent, increase your Life Points by 3000 points. This effect can only be used once as long as this card remains face-up on the field.
That's a 1500 LP gain on average (you use 2 cards, after all). May as well use Supremacy Berry.
Yeah, you do open up a direct attack, but only once: then you're back to defeating monsters. So unless it's the finishing attack, it actually makes you deal 350 less damage.