Emerald Ring

Creatures you control have trample.
{t}: Add {g}{g}. If you spend this mana to
cast a creature spell, it enters the battlefield with
an additional +1/+1 counter on it.
{3}{g}{t}: Create a */*+1 Elemental with trample
and "This creature's power is equal to the
number of creature cards in your graveyard,
and its toughness is equal to that number plus
one."