Mammon, Baron of Greed

Indestructible
At the beginning of your upkeep create a
Treasure token, then each opponent lose life
equal to the number of Treasure's you control.
{3}: Create a 1/1 colorless Molten Golem artifact creature Treasure token with "This creature gets
+1/+1 for each other Treasure you control." and
"{t}, Sacrifice this artifact: Add X mana of any combination where X equals its power."