Zoltan laments to Geralt about his debt to the King of Beggars acquired from playing gwent. He mentions three unique gwent cards he's come across that he's found a buyer for and asks Geralt for help in retrieving them.
After finally saving Dandelion go to Rosemary and Thyme, you will see Zoltan arguing with some suspicious men. Once you get close enough Geralt will join the conversation, pick either option and the leader Duke will decide it's time to go, while his friend Earl will boldly declare he can get rid of Geralt, but Duke will insist it's time to go. After they leave Zoltan will tell you what is going on, apparently he started trading Gwent cards for a living and needs help getting 3 rare cards: Fringilla Vigo, Isengrim, and Natalis. Once you agree to help Zoltan will direct you to Zed. Go to his place and knock on the door, apparently no one is home yet Geralt can clearly hear someone is inside and decides to look for another entrance. Walk back down the stairs and you should see a ladder in front of you, climb it and you should find another ladder nearby, so climb it too, now you need to jump over a gap between the two buildings, once you do there should be an open door there, so use it to get in Zed's house. Now jump down and you should find Zed's body lying on the floor, examine it and move on with the investigation. Now walk down and you will find 2 bandits talking, they are looking for Zed's ledger but failed to find it, however they have found the Isengrim Faoiltiarna card, so once the innevitable fight ends you will find it on one of their remains along with the key to the main entrance. Now time to search for the ledger, using the witcher senses you will notice something like claw marks under the stairs, something heavy was being dragged there so use Aard to break the boards to find a chest and the "Ledger of income and outlays" inside. Now you may read it if you like, but regardless it's time to get back to Zoltan. Once you talk to Zoltan your next targets will be Ravik who has the John Natalis card and Caesar Bilzen who has Fringilla Vigo, so you just have to decide where to go first.
Ravik and John Natalis
Go to The Golden Sturgeon, Ravik is now in the hands of Earl and the other thug you met at the beginning of the quest. He will offer you to play Gwent with him for Ravik's life and the card. If you refuse or agree but lose the game Ravik is killed and the fight begins, if you win the game then Ravik is spared but the fight begins regardless. Once Geralt is done with the overconfident Earl and lackey he will be rewarded with the card by Ravik who will first offer other cards but will eventually give it up, or if Ravik was killed it will be found on his remains.
Caesar Bilzen and Fringilla Vigo
Zoltan will aid you with Caesar Bilzen, so you will meet him when you reach the house. Once there talk to Zoltan who will tell you his plan on how to steal the card. Apparently Caesar has some secret collection in his house part of which is the card. Caesar will greet both at his doorstep and ask if Geralt is into fishing, regardless what you answer you will be invited to dinner and have a drunken conversation about fish. After that Geralt will be asked to get more booze, so go upstairs and look for the "booze." Using the witcher senses you will find a knife that cannot be lifted but turned to the side which will open a drawer inside you will find a triangular key and on a bookcase a triangular hole it fits into. When used another bookcase will move which will reveal a hidden door, inside you will find a staircase leading to the next floor where you will find the collection. There among other things you will find the card, but wait! In one of the cupboards you will find a Jade figurine which will start the The Soldier Statuette quest when you pick it up so be sure to get that too. Once you have taken everything you want go back downstairs, talk to Zoltan and after the conversation 2 dwarves sent by Cleaver will appear, you can choose to leave or fight them. If you do Caesar will thank you and then decide to pack his things and leave the city.
Meeting the Client
Once you have all 3 cards go with Zoltan to the place where the transaction will take place. Unfortunately the client is dead and Duke is there who took the money, he will call some thugs and make a run for it. Zoltan will tell you to chase him while he takes care of the thugs. Despite it being a chase there doesn't appear to be any time limit here so feel free to raid any containers you find along the way. The chase will eventually take you to the sewers where you will meet some drowners and a breakable wall so use Aard on it to progress. Eventually you will find Duke who is lying on the ground, talk to him and get the money back, now you will have the choice to kill him or let him go, what you choose is irrelevant as it's unlikely he will live. Now you will be teleported back to Zoltan who will give you another choice which will be your reward for the quest, you can choose to take the money in which case Zoltan will find another client for the cards or keep the cards for yourself (which is obviously the better choice unless you don't play gwent) regardless the quest ends there.
- Zoltan Chivay has never had much luck in business. No exception to this rule was the time he tried to acquire and sell three valuable gwent cards. At this time gwent was reaching the peak of its popularity and collectors were paying a fool's fortune for rare cards.
- Zoltan was not alone in sticking his pan into this raging torrent and hoping to strike gold. Yet there was another player in Novigrad, one wanting to grow his already-sizeable fortune, interested in flipping rare cards. Duke was his name, but many felt he would soon be known as Whoreson the Third - for he was even more ruthless than Whoreson Junior. This Duke stood in Zoltan's path to riches. Luckily, Zoltan had a friend named Geralt of Rivia who decided to step in and get him the cards he so desperately desired.
- The cards were in possession of Zed - a Novigrad fence. Geralt went to the dealer's house to buy them, but it turned out Duke had made it there before him. A brief exchange quickly turned to blows, and ended with the thugs pushing daisies. Among the splayed-out corpses was that of Zed, whom the murderers had killed earlier.
- Geralt searched the body and discovered his victory was not complete - he only found the Isengrim card. Zed had sold the two remaining ones to Caesar Bilzen and a man named Ravvy. There was nothing left but to visit both purchasers and get Zoltan his cards.
- Get the Fringilla Vigo, Isengrim, and Natalis cards for Zoltan.
- Find a way into Zed's home.
- Search Zed's home using your Witcher Senses.
- Find Zed's ledger using your Witcher Senses.
- Find the Isengrim card.
- Bring the card and Zed's ledger to Zoltan.
- Meet Zoltan in front of Caesar Bilzen's house.
- Get the John Natalis card from Ravvy.
- Search the body for the John Natalis card.
- Search upstairs in Caesar Bilzen's home using your Witcher Senses.
- Let Zoltan know you've found the card.
- Bring the cards to Zoltan.
- Go to the meeting with Zoltan's buyer.
- Chase Duke.
- Return to Zoltan.
- If you go south from where you finally meet Duke you will find another breakable wall which will take you to a tomb where you will find Vairmont Jonne who will give you the short quest A Tome Entombed. You can complete it before your final conversation with Duke as he is not going anywhere. This is quite convenient as finding the place again can be difficult.
- At the end of the quest you can either keep the cards or give them to Zoltan and receive 150 gold.
- If the cards are handed over, they can still be retrieved later. During The Great Escape, all 3 can be found on the prison commander's body after he's slain.
- With some stretch a reference to the Quentin Tarantino film Pulp Fiction can be seen when Zoltan asks what happened to Zed. Geralt replies "Zed's dead," referring to when Butch Coolidge (played by Bruce Willis) tells his partner Fabienne what happened to the character Zed from the movie.
- There's a third option to get the John Natalis Card from Ravik that will keep him alive, without playing Gwent. Before approaching the thugs, you can throw a bomb at them and they'll attack you, while Ravik will survive. After you talk, he'll give you the card.
- It is possible to obtain two copies of the John Natalis card. If you refuse to play Gwent for Ravvy's life, then if you throw a bomb that deals high enough damage to kill the two bandits and Ravvy with one throw, then you instantly shoot to the next cutscene where Ravvy is alive and he presents you his Natalis card. After the cutscene with Ravvy ends, you can loot the bodies for another copy of the card.
- Another method to gain two copies of the John Natalis card is when you're going down the stairs in the tavern, throw as many bombs as necessary to kill Ravvy and the two bandits, then approach their table. This will give way to the cutscene where Ravvy gives you the card, then you can loot the bodies for the second copy.
- Completing the Brothers In Arms: Novigrad quest before A Dangerous Game is complete will cause A Dangerous Game to fail.