[uh-oh]

Bran is the night king.

He goes back in time to stop the creation of the night king. The problem is the children of the forest are at war with the first men. The first men were savages using bronze and lacking magic, theyll see bran like yo wtf who is this dude, capture him and create the night king. This is after bran tries stopping the night king in other iterations of brandon stark. Bran the builder etc. Which is why hes older when turned

The night king/bran is on a mission to defeat the children of the forest, the last of which are on the isle of faces.

Its taken this long in history for a bran to be born to complete the cycle, the sea froze over like the pic poet posted and they cross there. He is going to get thereno matter what and killing humans is just an aside that gives him the numbers to actually make it there and then defeat the children.

Thats how the show will end. Humans are a sidenote. Essos is their continent.

The books will be different, this is just where theshow will go with it