Fanged Wyvern Hunter

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