Killed a White Walker, eh?
Game of Thrones Season 5, Episode 7
How about that old lady
with the WALKER?
The Big Bang Theory Season 7, Episode 12
used one of these daggers to kill a Walker.
Game of Thrones Season 5, Episode 8
Where did he kill a White Walker?
Game of Thrones Season 6, Episode 6
Why would obsidian kill a Walker?
Game of Thrones Season 5, Episode 5