Non-Attack interaction
Dominion is occasionally caricatured as "multi-player solitaire", in that in some circumstances it is possible for each player to independently build their own deck, with no direct interaction between different players' strategies and deck compositions. This tendency is mitigated, however, by the presence of cards that affect players other than their owners; this arguably makes the game more fun and strategic by keeping each player involved even during other players' turns. Attack cards are interactive in this way, but also tend to delay the game and are unpopular with some players; for this reason Donald X. Vaccarino thought it important to include non-Attack cards that cause interaction between players as well. At an early stage of development non-Attack interaction was the theme of the "War" expansion that eventually was revised into Dark Ages; it ended up being a subtheme of Prosperity, an expansion with relatively few Attack cards. But some such cards are present in each expansion.
A few non-Attack interactive cards—most commonly Masquerade, Tribute, and Possession—are occasionally mistaken for Attacks by new players, who expect to be able to use Reaction cards like Moat to respond to them and are disappointed to learn that they can't. However, unlike Attack cards, using these cards on average neither benefits nor hurts the players they target, in the absence of very particular combos.
Non-Attack interactive cards
Cards in italics have been removed.
Cards that give a small benefit to other players
Cards whose effect depends on another player's deck, turn, or hand
Cards that allow another player to make a decision
Supply piles:
The trash:
A number of Landmarks have limited amounts of tokens that players take from when they meet certain conditions.
Cards that change who controls a unique resource
Other interactive effects
- Masquerade swaps cards about between all players' hands.
- Embargo tokens affect all players equally once placed.
- Mountain Pass prompts a bidding event among all players after the first Province has been gained.
- Tax puts Debt tokens on a supply pile that affect whichever player is next to buy from that pile.
Fringe cases
- Fate and (non-Attack) Doom cards don't typically directly affect other players or the resources available to them, buy they do affect which Boons and Hexes are up next to be received.
- The Reaction cards Moat, Secret Chamber, Diplomat, Horse Traders, Beggar, Caravan Guard are interactive, but only in the presence of Attacks.
- Other Reaction cards (Watchtower, Tunnel, Trader, Market Square, Faithful Hound), as well as many other cards, have effects that can be triggered on other players' turns by some Attacks or other interactive cards.
- Ill-Gotten Gains, Raid and Haunted Castle are interactive and aren't technically Attacks, but they fill the same function as Attacks do.
- Rogue is an Attack, but its gaining effect depends on the shared resource of the Trash in the same way Graverobber does. Likewise Skulk, Tormentor, Werewolf, and Vampire affect the Hex pile by discarding its top card, but do so to Attack.
- Soothsayer and Old Witch are Attacks, but also gives their victims a small benefit like Council Room and Governor.
- Salt the Earth trashes a card from the supply; this doesn't directly affect other players (barring cards that gain from the trash), but speeds up the tempo of the game.
- Idol either Attacks, or affects the Boon pile, but not both at the same time.