Avarice

Lifelink
Avarice gets +1/+1 for each Gold token you
control
If you control six or more Gold tokens, Avarice
gains trample and indestructible.
Pay 2 life, {t}: Create a Gold token (it's an artifact
with "Sacrifice this artifact: Add one mana of any
color.")
{w/b}, Sacrifice a creature: Create a Gold token