Jerome Moreau

Jerome Moreau was a witcher of the School of the Griffin and the son of Professor Tomas Moreau, a researcher who studied witcher mutations in Toussaint. Jerome despised his father and had turned his back on his family. The professor, convinced he only wanted what was best for his son, never let it go.

In Blood and Wine

Jerome’s story is told through notes and diagrams rather than in person. In Scavenger Hunt: Grandmaster Griffin Gear, Geralt learns that Jerome was once summoned to Fort Ussar on a monster contract. The contract was only a pretext: his father wanted him back. The trail leads to a hidden workshop at Mont Crane Castle and through a portal to where Jerome was taken. The reunion ended badly for both of them, and Geralt walks away with a full set of Grandmaster Griffin diagrams.

The professor’s side of the story turns up in Turn and Face the Strange. Moreau wanted to reverse the witcher mutations and "cure" Jerome, but his process only made them stronger. His laboratory is what unlocks the mutation system in Blood and Wine.