slim herald
First Spectral Pack in Ante 1 contains Perkeo, and the first Arcana Pack contains Triboulet. The first Arcana Pack in Ante 3 has a Canio. As a bonus, the second shop has a Cryptid if playing on Ghost Deck. Will add anything else I find
Blueprint and foil Mime fairly early on in Ante 6
Brainstorm fairly early on in Ante 7