Ancião Adversosporo

All creatures you control gain the ability, regardless of whether they have spore counters on them, which means for example, they would lose the bonus from Muraganda Petroglyphs.

Your other creatures that produce spore counters (such as Thallids) can create a Saproling by removing two spore counters (by using this ability) or by removing three spore counters (by using their own ability).