Skellige Storm
Won from the Butcher, at the Butcher’s Shop, near Beauclair Port.
Geralt of Rivia
Velen (Troll Cave northwest of Hanging Man’s Tree) Gwent Quest: Playing Thaler, won from Thaler the erstwhile Shoe Peddler, at the end of Secondary Quest: A Deadly Plot.
Cirilla Fiona Elen RiannoN
Novigrad (Grassy Knoll), Gwent Quest: Big City Players, won from the Scoia’Tael Trader of Novigrad Forest (west of Farcorners, in woods).
Yennefer of Vengerberg
Novigrad (Oxenfurt City), Gwent Quest: Playing Innkeeps, won from Stjepan the Innkeep, at the Alchemy Inn.
Triss Merigold
Novigrad City (The Bits), Gwent Quest: Old Pals, won from Lambert at the Nowhere Inn (or Kaer Morhen).
Villentretenmerth
Won from a Gwent Player, Reward for beating an opponent (random).
Vesemir
Novigrad City (Hierarch Square), Gwent Quest: Big City Players, won from Vimme Vivaldi, the Dwarven Banker of Hierarch Square.
Olgierd von Everec
Won from a Gwent player, Novigrad (Oxenfurt City), Reward for beating Shani, at her Clinic in Oxenfurt.
Zoltan Chivay
Reward for beating Aldert Geert (Gwent scholar) in the White Orchard Tavern (or found at the Tavern if you miss him).
Emiel Regis Rohellec Terzieff
Won from a Gwent Player, Reward for beating an opponent (random).
Gaunter O’Dimm: Darkness
Purchased from Trader (20 Crowns), Novigrad (Gustfields), The Elven Merchant of the Traveling Circus Camp (outside Carsten), or won from a Gwent Player, Novigrad (Oxenfurt City), Main Quest: Open Sesame (Part 1), reward for beating Hilbert the Auction Bidder at Borsodi Auction House.
Gaunter O’Dimm: Darkness
Purchased from Trader (20 Crowns), Novigrad (Gustfields), The Ofieri Merchant of Upper Mill.
Dandelion
Novigrad (Gustfields), Secondary Quest: A Matter of Life and Death, won from Sir Marius Florin, the Gwent Players of Vegelbud Estate.
Mysterious Elf
Skellige (Ard Skellig), Gwent Quest: Gwent: Skellige Style, won from Gremist the Chemist, Druid of Gedyneith.
Cow (and Bovine Defense Force)
Picked up (loose card), Novigrad (Gustfields), Found in the upper loft of the main barn building of Brunwich.