The Bullfrog

Whenever you cast a creature spell with
mana value 4 or greater, you draw a card, gain 1 life, and put a +1/+1 counter on Helga.

{t}: Add X mana of any one color, where X is
Helga’s power. Spend this mana only to cast creature spells with mana value 4 or greater or creature spells with {x} in their mana costs.