Savage Punch

If either target is an illegal target when Savage Punch tries to resolve, neither creature will deal or be dealt damage.

Ferocious abilities of instants and sorceries that don’t use the word “instead” will provide an additional effect if you control a creature with power 4 or greater as they resolve.

Assuming the ferocious ability applies, if just the creature you control is an illegal target when Savage Punch tries to resolve, it won’t get +2/+2 until end of turn. If the creature you control is a legal target but the creature you don’t control isn’t, the creature you control will get +2/+2 until end of turn.