Well since someone will do it eventually, here are all the cards that can reveal Patron (tell me if I miss any).
Removed (5): Scout, Spy, Thief, Saboteur, Tribute, Adventurer
Dominion (2): Bureaucrat, Bandit
Intrigue (4): Shanty Town, Wishing Well, Courtier, Patrol
Seaside (3): Ambassador, Cutpurse, Pirate Ship
Alchemy (3): Apothecary, Scrying Pool, Golem
Prosperity (3): Loan, Rabble, Venture
Cornucopia (5): Fortune Teller, Menagerie, Farming Village, Harvest, Hunting Party
Hinterlands (4): Crossroads, Oracle, Noble Brigand, Inn
Dark Ages (11): Poor House, Vagrant, Sage, Ironmonger, Wandering Minstrel, Knights, Mystic, Pillage, Rebuild, Rogue, Madman
Guilds (5): Doctor, Advisor, Taxman, Herald, Journeyman
Adventures (2): Magpie, Giant
Empires (6): City Quarter, Royal Blacksmith, Patrician, Chariot Race, Gladiator, Grand Castle
Nocturne (6): Raider, Will-o'-Wisp, Ghost, Bad Omens, Famine, War
Renaissance (4): Border Guard, Seer, Villain, Piazza
Promo (2): Black Market, Envoy
Total: 65 cards
Edited: Venture, Black Market, Envoy, Tribute, Bureaucrat, Pirate Ship, Adventurer