It's what I used to kill the White Walker.
Game of Thrones Season 5, Episode 7
One of the tennis balls
came off his WALKER
The Big Bang Theory Season 7, Episode 14
how in seven hells
did you manage to kill a White Walker?
Game of Thrones Season 4, Episode 9
How about that old lady
with the WALKER?
The Big Bang Theory Season 7, Episode 12
How many brothers can say that
they've killed a White Walker and a Thenn?
Game of Thrones Season 5, Episode 1