If Jon Snow had the ability to turn to stone, it would significantly change the course of the Game of Thrones universe. He would be virtually invincible, as no weapon or magic could harm him in his stone form. However, this ability may also come with its own disadvantages. Turning to stone could leave him immobile and vulnerable to attacks if he is not careful. It could also limit his ability to interact with others and engage in battle as he would be unable to move or fight back while in his stone form. Furthermore, his ability could be seen as a threat to others, causing fear and distrust among those around him, which could make it difficult for him to gain allies and support. Overall, while having the ability to turn to stone would provide Jon Snow with great advantages, it would also present new challenges and potentially isolate him from others.