<Tr> <Th> Type </Th> <Td> Non-human creature </Td> </Tr> <P> A White Walker is a humanoid creature from the HBO television series Game of Thrones, and the George R.R. Martin novel series A Song of Ice and Fire on which it is based . Primarily referred to as the Others in the novels, White Walkers are a supernatural threat to mankind who dwell north of The Wall in Westeros . The Verge named them among "the most visually iconic creatures on the show". White Walkers are also featured in the show's merchandising . </P> <P> Martin introduces the Others in the prologue of A Game of Thrones (1996), describing them as "Tall...and gaunt and hard as old bones, with flesh pale as milk" with eyes "deeper and bluer than any human eyes, a blue that burned like ice". Accompanied by intense cold, they wear armor that "seemed to change color as it moved", and wield thin crystal swords capable of shattering steel . The Others move silently, and they speak their own language; Martin writes that their voices are "like the cracking of ice on a winter lake". In A Storm of Swords (2000), they are shown to be vulnerable to weapons made of dragonglass (obsidian), as Samwell Tarly kills one this way: </P> <P> (T) he Other's armor was running down its legs in rivulets as pale blue blood hissed and steamed around the black dragonglass dagger in its throat...where its fingers touched the obsidian they smoked...the Other shrank and puddled, dissolving away . In twenty heartbeats its flesh was gone, swirling away in a fine white mist . Beneath were bones like milkglass, pale and shiny, and they were melting too . Finally only the dragonglass dagger remained, wreathed in steam...Grenn bent to scoop it up and flung it down again at once . "Mother, that's cold ." </P>

When do the white walkers appear in game of thrones
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