Use the power of the target creature as Fell the Mighty resolves to determine which creatures are destroyed. Fell the Mighty doesn't target any of those creatures, so a creature with hexproof or protection from white will be destroyed if its power is high enough.
07-11-2014
wotc
Fell the Mighty won't destroy the target creature.
07-11-2014
wotc
If the target creature is an illegal target when Fell the Mighty tries to resolve, Fell the Mighty won't resolve and none of its effects will happen. No creatures will be destroyed.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.