This one is a bit of a toughie, I think. What one card can be added to complete this list?
Black Market
Embargo
Golem
Pirate Ship
Trade Route
Transmute
Treasure Map
Honorable mention: Curse
(Hope I haven't missed any....)
And now also: Crossroads, Cultist, Duchess, Fool's Gold, Madman, Rats, Spoils