Magic and chaos are everywhere. We can be conduits to it's power to bend and shape it. There's a cost for it, shifting and melting means something in turn must give. Perhaps your world has forgotten the order of it?

[She can only guess. She knows next to nothing and all that John has told her is that it's different. The firelight flickers and the wind blows too.]

Witchers aren't born. They're raised, molded and educated from childhood. Fed mutagens for strength, for producing small capacities of magic and being able to endure others without significant effects. I've heard some folk say that witchers are the monsters man made for monsters to fear.

[The man beside her though? Geralt gets another look, softer.]

Geralt of Rivia is no creature. Just a man devoted to the task of curbing the wildlife. He's a conduit of order.