Bone Armor Triheaded Dragon

X can't be zero.
Flying
Bone Armor Triheaded Dragon enters the battlefield with X +1/+1 counters on it.
When a creature dies, put a +1/+1 counter on Bone Armor Triheaded Dragon.
When this creature dies, put a +1/+1 counter on another target creature equal to the amount of +1/+1 counters on this creature.