Defeat of Isiladan

(You may cast a legendary instant only if you control
a legendary creature or planeswalker.)
Kicker {1}{b}
Destroy target creature or planeswalker. If it's a creature, you lose life equal to that creature's
power. If it's a planeswalker, you lose life equal
to the number of loyalty counters on it. If this
spell was kicked, you gain that much life instead.