Incorrect. There are two parts to the card, cost and effect.
Cost: This condition must be met before the card is even played.
Card is then played.
Now you get effect.
So, in order to play the card, you must meet the cost of playing the card, spotting three twilight tokens.
Then the card is played, adding 3 more.
Then you get the effect.
Which explains the difference between
Under the Living Earth and this card, the effect occurs after the card is played, thus the twilight is counted. So the card isn't QUITE as good as you thought, but still sweet with Ents. Actually, with ents, go
Deep In Thought. Totally go
Deep in Thought.