Piscine Wyvern Hunter

Put a +1/1 counter on Piscine Wyvern Hunter
whenever a Piscine Wyvern is killed
Piscine Wyvern Hunter gets +1/+1 for each
Piscine Wyvern controlled by an opponent.
{3}{u/r}: Deal 5 damage to target Piscine Wyvern
{4}{u/r}{u/r}: Destroy target Piscine Wyvern