Suncrusher

Sunburst (This enters the battlefield with a
+1/+1 counter on it for each color of mana
spent to cast it.)
{4}, Tap, Remove a +1/+1 counter from
Suncrusher: Destroy target creature.
{2}, Remove a +1/+1 counter from Suncrusher:
Return Suncrusher to its owner's hand.