The Mycotyrant — The Lost Caverns of Ixalan Promos #235p

Trample

The Mycotyrant's power and toughness are each equal to the number of creatures you control that are Fungi and/or Saprolings.

At the beginning of your end step, create X 1/1 black Fungus creature tokens with "This token can't block," where X is the number of times you descended this turn. (You descend each time a permanent card is put into your graveyard from anywhere.)