The Viper School is a school of witchers appearing in Assassins of Kings and Wild Hunt. The school is headquartered somewhere within the Empire of Nilfgaard. At some point the school dissolved and its students scattered throughout country; the catalyst for its downfall remains a mystery. Adherents of the school include:
- Letho of Gulet
- An unknown witcher from The Witcher outro
- Two unnamed witchers mentioned by Letho in his final conversation with Geralt
- Kolgrim, a witcher who died trying to clear his name of a kidnapping
- Ivar Evil-Eye, either a high-ranking member or the leader of the Viper School
It is possible that the mysterious assassin from the end of The Witcher may have been one of two unnamed members, rather than a third.
Before its destruction, the Viper School was believed to possess a wealth of valuable information, including an extensive collection of books about the Wild Hunt. It is also believed that the school may have taught the use of short blades in its swordsmanship training, as several of its students had displayed a predilection for shortswords as opposed longswords. However, this may have simply been a preference of the Kingslayers, and not indicative of the practices of the school itself. A pair of weapon schematics for Viper School longswords can be found in Wild Hunt, which have an inlaid poison effect.