Can you even beat the Nilfgardian dude in Vizima (After you get there from White Orchard)? Because he seems to have some OP cards, tried going against him once and I thought I was doing great, until he started pulling cards twice the strength of mine.....
My OCD is killing me, I need to defeat him! But it looks like I'll have to go back there with a better deck.
Played him 5 times with my base deck+Zoltan from winning my first match.. Won 2 lost 3. So yeah it's possible if you get your tactics right and have some luck.