Before commencing the Toussaint Gwent tourny Geralt must qualify his Skellige deck with Count Monnier. He’ll then tell you to return in two (in-game) days for the tournament itself.
This small quest is a post-Blood and Wine ‘bookend’ that reunites Geralt with his romance partner at Corvo Bianco. If you didn’t romance anyone then either Dandelion or Ciri can turn up, depending on what you did in the base game.
There are quite a few quests in The Witcher 3. In fact: there are 309 in total. These are my top 30 favourites.
A guided tour of Geralt’s new home in Toussaint, Corvo Bianco, then a few small orders to fix the place up. A lick of paint to the exterior, an armourer’s table, and a grindstone to start things off.