It took over 9 hours to create these intricate 'Game of Thrones' forest creatures

HBO

Sunday's "Game of Thrones" took us farther beyond the Wall and deeper into the mythos of the White Walkers than ever before. We found out the origin of the death-seeking White Walkers and saw the last stand of Leaf, the "leader" of the enigmatic Children of the Forest.

HBO released a visual effects breakdown that takes us behind the scenes of both the climactic cave battle and into the make-up chair as we see how they create the terrifying White Walkers and the mysterious children. The actors endure a 10-hour hair, make-up, and prosthetic process to get transformed.

Keep reading to see how the "Game of Thrones" make-up team brings the creatures beyond the Wall to life.

Here's actress Kae Alexander who plays the Children of the Forest leader Leaf on "Game of Thrones."

The entire make-up process can last as long as nine to ten hours.

Alexander has prosthetics glued onto her entire body in addition to hours of hair and make-up.