What's so special about Valyrian steel?

Related questions

1. Was the night's king a stark?
2. Why does Dragon Glass kill White Walkers?
3. Will Jon Snow become the night king?
4. Which Dragon does daenerys ride?
5. How is Jon Snow real father?
6. Did Arya's dance teacher died?
7. Can Jon Snow not be burned?
8. Why did White Walkers take babies?
9. How do targaryens have dragons?
10. Why did the children make the White Walkers?

Tags

1. #fashioned
2. #forever
3. #mighty
4. #bladed
5. #forged
6. #honing
7. #steel
8. #eddard
9. #valyrian
10. #greatsword
11. #especially
12. #sharp
13. #stark
14. #metal
15. #remaining
16. #freehold
17. #weapons
18. #without