Blood Run Main Story, Blood and Wine Quest
Suggested level: 36
This quest will be triggered or can be aquired when you complete The Beast of Toussaint quest.
Stages of "Blood Run" quest
1. Fight the Beast.
When word of yet another murder reached the tourney participants, panic broke out among them. Geralt, affected by no such emotion, remained on the killer's tail as they rushed helter-skelter through the streets of Beauclair. The witcher finally cornered the murderer in an old, abandoned storehouse.
It does not matter whether you win or lose (different cutscenes only + extra experience points if you are better then your opponent).
2. Quest completed.
I do not know, nor do I know of, a single soul more experienced than Geralt in his profession. To surprise the witcher takes incredible guile, yet the murderer sowing terror throughout Toussaint managed just that. The witcher caught up to the killer, there was a brief exchange, then a fight most fierce ensued. I cannot say how the duel would have ended had our old friend Regis not appeared and intervened. Thus, Geralt's first confrontation with the Beast went unresolved.
Next / new quest is La Cage au Fou (Main Story, Blood and Wine).