Either Sporoloth Ancient or Thallid has at least three spore counters on it, with the other having at least two spore counters on it.
Steps
Activate either Thallid or Sporoloth Ancient by removing two spore counters from it, creating a 1/1 Saproling creature token.
When the Saproling enters the battlefield as a Forest land due to Life and Limb, Evolution Sage triggers, putting a spore counter on Thallid and Sporoloth Ancient.