By Cat Taylor
While chatting with the SFX team, I managed to wrangle some information on how one of my favorite effects of the season came to be: The Sword of Fire.
There were, it turns out, actually two swords – one that would burn for an actual fight sequence, and another that has the ability to bleed and ignite itself.
The fight-sequence sword is a real sword that the workshop team milled with a number of channels, each one stuffed with a dura-blanket material. The flame retardant fiber is then soaked in IPA (isopropyl alcohol). This was then covered in another layer of material to make the blade look uniform and sword-like again. Because of the length of the sequence, the flame has to last (and burn strong) for at least 3 minutes, which was something of a challenge, as the fuel burned off so quickly.
The second sword had blood inside the blade and could be ignited. The sword itself split into two pieces, and the inside was filled with a series of small, sealed channels. Some were filled with gas, the rest with fake blood – that way, when the blade was drawn across any surface, skin or otherwise, hitting a button on the hilt of the blade would release blood through tiny holes down the side, making it appear as if blood was welling up from a cut.
There was a tiny pilot light, which you could never see on the blade, but when a button was pressed and the gas released down the channels, the sword would burst into flames. You could not use this for any contact during a fight scene, though, as the mechanism inside is too delicate to withstand the impact, and with the blood and gas being supplied into the blade, it would be unsafe to use for stunts.
CORRECTION: During the craziness of production and starting with a story comparing Stannis' and Beric's flaming swords that turned into something more technical and specific, the original title of the piece was erroneously posted with this blog and has caused some confusion. To clarify - this story is about Beric's sword and I never changed the title to reflect the change in focus. Can this be one of my nine lives?