Having reached the third chapter, I can't, for the life of me, challenge De Wett in poker. I'm early in the chapter (the only main quest completed being the posh reception), have already challenged every other available poker player, but the option to challenge De Wett never appear when I talk to him.

Is it because I sided with Thaler? Was there a specific sequence of dialogues during the reception that I missed? Or is it simply unlocked by going a little further along the main quest? I do remember having played poker with him in my previous game, but don't remember much about how or when I played him (except that I played neutral to a fault and let Thaler get killed), and am slightly afraid that, given the game pernickety structure, I may have accidentally closed off the possibility of challenging him.

As with many poker players, a specific dialogue sequence is needed to open up his poker option. It may be behind a now-gray dialogue option.

For de Wett, ask him if he's into politics.

It certainly isn't a problem to face off De Wett. He will play poker with you no matter how offensive you were in earlier dialogue choices.

I've always sided with Thaler, as it was obvious by then that the edicts were false, and De Wett and Adda were conspiring.

I took great pleasure in making short work of De Wett when the opportunity arose, though I did spare Adda, as that seemed more "witcher's work" than slaughter.

You get the option if you are still in "The Professional" and if you talk to De Wett in the upper level of the guard tower, near the New Naracourt ~ I did both Velerad and De Wett on a single pass through on the way from the Huntsman to storage. I don't recall if you *had* to play all available pros, so you may have completed "The Professional" before you got the chance to use this dialogue option ~ but I think, based on everyone else, that you should have the chance to play him right up until the end of the chapter.

There is only one poker game that you cannot replay in either Witcher game. The last one in the Witcher 1, and the first in Act 2 of the Assassin of Kings. Otherwise it is merely tackling it before you close out the chapter in which the potential opponent last appears, with as many retries as you need.

You need to play just four Professionals to advance; there are five in Acts II and III. (Munro Bruys, Thaler, de Wett, Velerad, and the Hierophant) If you missed too many, there are three more in Act IV.

Even if you already advanced, you can still unlock Professionals' play options with the right dialogue.