For those who don’t know, Castle Black was one of the main locations on the Wall where members of The Night’s Watch – the sworn brotherhood of men who guard the North against the Wilding and Night King.

Source: https://www.koimoi.com/television/game-of-thrones-castle-black-didnt-just-look-foul-it-was-stinking-with-pigs-raw-meat-heres-how-jon-snow-kit-harrington-others-lived-there/

He walks past the motionless Wights and comes across the Night King and the White Walkers sitting astride their dead horses.

Source: https://gamerant.com/game-of-thrones-night-king-white-walkers-explained/

The Night King was known for his strange blue eyes, a trait all his followers gained once he raised them from the dead.

Source: https://screenrant.com/game-of-thrones-battle-of-winterfell-things-make-no-sense/

The threat posed by the Night King has already passed, large sections of the Wall have been destroyed, and the free-folk are no longer enemies of Westeros.

Source: https://www.cbr.com/jon-snow-game-of-thrones-series-better-movie/

Though defeating the Night King in Season 8 was an incredible triumph, the killing felt shocking and out of place for Arya.

Source: https://collider.com/game-of-thrones-arya-stark/