The eighth and final season of “Game of Thrones” will feature an epic battle so intense, actors collapsed while making it.

An unnamed series regular actress even passed out while filming, EW reports. She was fine, but the battle sequence (which will take place at Winterfell) was brutal to film.

It’s a showdown between Jon Snow (Kit Harington), his allies, and the Army of the Dead. But this time, it’s not just Jon and his band of not-so-merry men. Arya (Maisie Williams) is involved too, as are Sansa, Daenerys, and Brienne.

“I skip the battle every year, which is bizarre since Arya’s the one who’s been training the most,” Williams tells EW. “This is my first taste of it. And I’ve been thrown in at the deep end. Nothing can prepare you for how physically draining it is… there are moments you’re just broken as a human and just want to cry.”

According to its Emmy-winning director Miguel Sapochnik (who also helmed Season 5’s battle episode “Hardhome” and Season 6’s “The Battle of the Bastards”), this will be the longest battle sequence in film history, exceeding even the 40-minute fight in “The Lord of the Rings: The Two Towers.”

Aside from Arya and Jon, The Hound (Rory McCann) will be there, along with Daenerys Targaryen (Emilia Clarke), Tyrion Lannister (Peter Dinklage), Arya Stark (Maisie Williams), Sansa Stark (Sophie Turner), Brienne (Gwendoline Christie), and Sam Tarly (John Bradley).

The producers say the sequence will feature the largest number of characters together since the pilot episode in 2011.

The final “Game of Thrones” season premieres April 14 on HBO.