Who created the Night Walkers?

Related questions

1. Who sits on Iron Throne in the end?
2. Are Jon Snow and Daenerys siblings or cousins?
3. Is Season 7 the last season for Game of Thrones?
4. Who Wrote Season 7?
5. Why does Season 7 have less episodes?
6. Who is the king of seven kingdoms?
7. How many episodes are in season 7 of Game of Thrones?
8. How did Rhaegal die?

Tags

1. #white
2. #stark
3. #returning
4. #house
5. #afterward
6. #built
7. #brandon
8. #named
9. #order
10. #founder
11. #walkers
12. #south
13. #builder