Warning: Many icy spoilers ahead.
Remember a couple weeks ago when "Game of Thrones" showed us what happens when the Lannister army meets the Dothraki and a dragon? (I'm still recovering.) Last night's episode showed us what happens when seven of our favorite characters battle thousands of wights, white walkers and an ice javelin-throwing Night King.
HBO released a 13-minute behind-the-scenes video on Monday that shows how the battle on the frozen lake was created. Hint: It was filmed in Iceland and at a quarry in Belfast, Northern Ireland. Crews flattened and filled the quarry with concrete and then painted it to look like a frozen lake for thousands of wights to run across.
The video also has interviews with writers, actors and stunt coordinators and shows the insane number of people it took to create all the battles -- there is a crew of people who had to "paint" and dress an entire quarry every day to match shots filmed in Iceland.
And then there's the matter of that frosty ursine foe Jon Snow and crew encountered.
"What we had to go through to get the zombie polar bear was writing the zombie polar bear into every season of the show for about four seasons," said executive producer and writer D.B. Weiss, "only to have Bernie [Caulfield] and the visual effects guys to tell us in the nicest possible way, 'Fuck you, we cannot afford a zombie polar bear.'"
But things changed this season. The video details the blend of practical stunts and visual special effects it took to bring a zombie bear to life -- so to speak.
Take a look at the full behind-the-scenes video above.