Eredin and the Wild Hunt are featured in a number of the Witcher books but take a more prominent role in the events of the video game The Witcher 3: The Wild Hunt where the army chases Ciri across the main regions of the game.
Furdík is more than capable of bringing fear to his characters, and with the Eredin wearing a helmet that covers his face throughout the video game, the actor could continue to emote through his physicality like he did in Game Of Thrones.
Perhaps this is why Furdík would be such an ideal candidate to portray Eredin Bréacc Glas, also known as the King of the Wild Hunt, a calvary of elven specters on a tireless mission to hunt Ciri.