If there are 3 cards in the discard pile that have the Elder One Summoning symbol, the Elder One advances toward ultimate power!

If there are 3 Elder One Summoning symbols:

Advance the Elder One along the Summoning track. If the Elder One is already on the board, move the Progression token along the track instead. The revealed Elder One Stage cards and the Episode card will tell you what to do when the Elder One advances. Resolve the Elder One effects first. It doesn’t matter whether it’s the Elder One figure or the Progression token advancing on the Summoning track, the effects are resolved in the same way.

After the Elder One advances, all of the discarded Mythos cards are shuffled back into the deck.