The conversation between human and AI assistant.
Who and what were those four white walkers?
Is there any way to defeat them without dragonglass or Valyrian steel?
There is no known way to defeat White Walkers other than using dragonglass or Valyrian steel. However, fire was shown to be effective in killing wights, which are the undead minions created by the White Walkers. It is possible that fire may also be effective against White Walkers, but this has not been confirmed in the show or the books.