- The cards placed under your agenda facedown with Archmaester Marwyn and The Conclave agenda are considered the same pool of cards.
- You cannot trigger Archmaester Marwyn if your deck does not have an agenda.
- Cards under your agenda CAN be marshaled into shadows. The problem with the other cards that allows you to marshall a card as if they were in your hand is that they all have a characteristic requirement. King's landing allowing you to marshal locations, Tarle allowing you to marshall drowned god character and Gormon allow you to marshal a non-Tyrell card. You can't marshal a card into shadows because a card in shadows does not have any of those characteristics. However it should be noted that Marwyn has no characteristic requirement for what you can marshal as if they were in your hand.
Does this allow you to play cards with the ambush ability? — Muskerion
No. Ambush is different than marshal or play. — scantrell24
Cool. Appreciate the quick clarification. Thank you. — Muskerion
Sure? — Mascalian
Yes... Ambush = "put into play", which is different from the "marshal or play": the "play" is referred exclusively to events.. if I'm not mistaken — Mascalian