Swift Hands
Supply
Synergy
High (76)Engine 100%Slog 80%Attack-heavy 75%
Variety payoff + broad gainer/+Buy — Snake Witch + Haggler
Fairgrounds/Museum/Horn of Plenty want many differently-named cards; Workshops and +Buy make one-of shopping cheap.
Per-gain payoff + multi-gainer — Cauldron + Haggler
Livery/Garrison/Labyrinth/Commerce only shine when you gain several cards per turn — Workshops/Horse/Loot gainers and +Buy provide those gains.
Draw-to-X blunts hand-size attacks — Samurai + Ronin
Library-style draw-to-X cards refill after Militia-style discard attacks, and draw more when the hand starts small.