Primal Might
Sorcery
Target creature you control gets +X/+X until end of turn. Then it fights up to one target creature you don't control.
The shaman looked at the world through Ghalta's eyes and understood that everything else was his prey.
Illustrated by
Core Set 2021 Promos#197pRareEnglishLegality
Rulings
You can cast Primal Might targeting only the creature you control.
You can cast Primal Might with 0 as the value of X to just have the two target creatures fight.
If you choose two target creatures and either target is an illegal target as Primal Might tries to resolve, neither creature will deal or be dealt damage.
If the creature you control is an illegal target as Primal Might tries to resolve, no creature gets +X/+X. If that creature is a legal target but the creature you don’t control isn’t, it still gets +X/+X.