Yurei, Master of Fungi

When Yurei, Master of Fungi enters the battlefield, populate, then proliferate.
Saproling creatures have +1/+1
Creatures with Spore counters on them have +1/+1
Sacrifice a Saproling: Put a spore counter on each nontoken creature you control.
{4}{w}{b}{g}{t}: Exile Yurei, then return it to the battlefield tapped at the beginning of your next upkeep.