Dried Winds

•Once per turn, when you gain life, pay {1}{r}{g}: destroy target creature opponent controls.
•While you control at least one Alchemist, and
your life is at least 15 higher than you opponents,
you may pay life equal to the difference, destroy
target creature(s) your opponent controls
who's combined power and toughness is less than
or equal to the life paid to activate this effect.