Dominion Summon Promo

– When you buy this, you gain an Action card costing up to $4 from the Supply and set it aside face up.
– If you did set it aside, then at the start of your next turn, play that Action card. This doesn’t use up your default Action for the turn.
– In order to remember to play the card on your next turn, you may want to turn it sideways or diagonally, turning it right side up when you play it.
– If you move the Action card after you gain it but before you set it aside (e.g. by putting it on top of your deck with Watchtower from Dominion: Prosperity), then Summon will “lose track” of it and be unable to set it aside; in that case you will not play it at the start of your next turn.
– If you use Summon to gain a Nomad Camp (from Dominion: Hinterlands), Summon will know to find the Nomad Camp on your deck, so you will set it aside in that case (unless you have moved it elsewhere via another ability).

Other clarifications (from wiki):

– The Summoned card is discarded during your Clean-up phase once its effects are resolved like a typical Action card, as it has been brought into play by the effect of Summon.
– If you are being Possessed, and the player to your right tells you to Summon a card, they gain the card, which does not get set aside, nor played at the start of their turn, instead staying in their discard pile.
– If you Summon a Hireling, you will draw a card when you play it, since it will still be the start of your turn.
– Summon will also fail to move a card if it moves away, and then moves back to the same place. For example, if you gain an Experiment, exile it to Gatekeeper, then gain the second Experiment and discard the first Experiment from Exile, Summon will still fail to set aside the Experiment, even though it’s still in your discard pile