One possibility could be that in the fanfiction, Jon Snow discovers the Valyrian steel in an ancient castle's armory. Maybe it was hidden away for centuries, and his discovery sets off a chain of events that changes the course of his journey.
Valyrian Steel could be part of an ancient prophecy in the Harry Potter fanfiction. Maybe it's said that only a wizard with a pure heart and a connection to the founders can wield a weapon made of Valyrian Steel. Harry, being the hero, is destined to find and use it to defeat the ultimate evil. It could also be that the Valyrian Steel is hidden in a different magical realm that Harry has to travel to, which would introduce new and exciting settings into the fanfiction.
The White Walkers were a race of ice creatures in the world of 'Game of Thrones'. They were created by the Children of the Forest as a weapon against the First Men. They had blue eyes and could raise the dead. They were extremely powerful and cold, bringing a long winter wherever they went. Their leader was the Night King. They were a major threat to all living things south of the Wall.
The White Walkers were created by the Children of the Forest. Long ago, the First Men were encroaching on the lands of the Children. In an attempt to defend themselves, the Children of the Forest created the White Walkers using dark magic. They were made from captured humans and given powers over ice and cold. However, the White Walkers soon got out of control and became a great threat not only to the First Men but also to the Children of the Forest themselves.
He could use it to defeat a powerful enemy. Valyrian steel is very effective against certain threats in the 'Game of Thrones' universe. So, when Jon Snow finds it in the fanfiction, he might be able to slay a great foe that was previously unbeatable.
One possible fanfiction could be about a group of survivors who are captured by the White Walkers. They might be used as some sort of bait to draw out other humans. For example, the White Walkers could leave a trail of the captured ones, leading the Night's Watch or other northern forces into a trap.
One idea could be that Harry discovers a hidden Valyrian Steel sword in Hogwarts. It might have some ancient magic tied to it that could help him in his fight against Voldemort. Maybe it has the power to cut through dark magic spells easily.
Well, the White Walkers story in Game of Thrones had so much potential. However, it did seem like the show threw it away. They had been a looming danger for seasons, and fans were expecting a more epic and drawn - out battle and resolution. Instead, it ended quite quickly. There were also some plot holes in how they were defeated, like Arya's sudden ability to take out the Night King. It made the whole build - up of the White Walkers' threat feel a bit wasted.