Melan, Yavimaya Overgrowth

At the beginning of your upkeep put a spore
counter on up to X creatures you control.
Creatures with a spore counter are Fungus in addition to their other types.
Whenever another Fungus creatures dies exile it
and make a 0/1 green fungus token copy of it.
X is equal to the number of times you've cast
your commander this game.