Gwent: Playing Thaler Witcher 3: Wild Hunt Quest
Group: Secondary Quests
Location: Novigrad
This quest will only appear in your journal if the "Gwent: Old Pals" quest has been completed before the "A Deadly Plot" quest. Otherwise, playing with Thaler will be part of the "Gwent: Old Pals" quest. You'll get it after you escort Thaler at the end of "A Deadly Plot" to his wagon.
Bernard Dukat, a.k.a. Thaler, was a truly great gwent player. What makes a gwent player great, you ask? Equal parts cunning and good cards, I reply. These last Geralt wanted for himself, for he felt his own collection was somewhat lacking.
Quest stages of Gwent: Playing Thaler
1. Win a unique card from Thaler.
You can play with him right away or a little later, then you will find him at the Seven Cats Inn. Thaler uses Scoia'tael deck. Once defeated he will hand over the Geralt of Rivia card and tell you about the next player - Lambert.
As you might have guessed, Geralt managed to acquire Thaler's best card.