The Witcher 3: Das Malefitz

The ongoing war and bloodshed in The Continent is poisoning a parallel world that a group of supernatural beings known as The Huldufólk inhabit. They are slowly dying. A mysterious sea creature known as Knoggelvi is forced to serve a spirit of summer known as the Sea Mither who is in constant conflict with Teran, a spirit of winter.

Knoggelvi sees the Huldufólk’s plight and proposes a pact. It will save them if they agree to send several volunteers with Knoggelvi to undergo a drastic transformation through a ritual and temporarily serve as warriors in the depths of the ocean on its behalf. This pact requires the cooperation of a remote human village who will need to undergo the same ritual and merge with the Huldufólk, creating new beings Knoggelvi calls “Children of the Deep.”

To ensure their cooperation Knoggelvi secretly introduces a plague to the villagers and claims that they will also be saved. The village nearly destroys itself in the witch-hunt that ensues to find “volunteers.” Tuvla, a Huldufólk woman, happens to see Knoggelvi introducing the plague to the human villagers and realizes the pact has been made in bad faith. She tells the other Huldufólk who collectively agree not to reveal this for fear of jeopardizing the pact but her conscience gets the better of her and she confesses this to her lover, Czesław - a failed Witcher from the School of the Cat.

After a lifetime of oppression and disillusionment, this final act of betrayal breaks him and he commits a mass murder-suicide killing the Children of the Deep, Túvla, and finally himself. It’s at this point that Geralt enters the story.