Khazad Dum

When Khazad Dum enters the battlefield, create up to one 2/2 white dwarf creature tokens.
{t}: Add {c} to your mana pool.
{1}: Create a colorless artifact treasure token with
"{t}, Sacrifice this artifact: Add one mana of any color to your mana pool." and put a wealth counter on Khazad Dum.
At the beginning of each end step, if there is eight or more wealth counters on Khazad Dum, destroy all dwarf creatures and transform Khazad Dum.