Ghoul of Behemoths

{x}, {t}: Target creature with converted mana cost X has " {b}{g}: Monstrosity 3" until end
of turn.(If it isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
Whenever a monstrous creature you own dies, bolster 2.(Choose a creature with the least toughness among creatures you control
and put two +1/+1 counters on it.)