Varin

Varin was the sword instructor at Kaer Morhen, his ghost is seen during a scavenger hunt for Wolf School gear in Witcher 3. As the player explores the bastiel where children were trained prior to the Trial of the Grasses several flashbacks can be viewed using Keira's lamp. In the flashbacks Varin is depicted as a ruthless, demanding instructor; taking the children's training seriously. During the massacre at Kaer Morhen it's unknown if he was murdered along with the children and mages though it can be safely assumed since the player sees his ghost.