the special make-up effects supervisor, and Colin Arthur, former Studio Head of Madame Tussaud's, were responsible for the human dummies and fake body parts used in the film. The dummies inflated crowd numbers and stood in as dead bodies, while the body parts were used in scenes showing the aftermath of fights and the cult's cannibalistic feast. In Thulsa Doom's beheading scene, Schwarzenegger hacked at a dummy and pulled a concealed chain to detach its head. The decapitation of Conan's mother was more complex: a Plexiglas shield between Jones and Nadiuska stopped his sword as he swung at her and an artificial head then dropped into the camera's view. A more elaborate head was used for the close-up shots; this prop spurted blood and the movements of its eyes, mouth, and tongue were controlled by cables hidden beneath the snow. Allder created a $20,000 mechanical snake for the fight scene in the Tower of Serpents. The snake's body had a diameter of , and its head was long and wide. Its skeleton was made from duralumin (an alloy used in aircraft frames) and its skin was vulcanized foam rubber. Controlled by steel cables and hydraulics, the snake could exert a force between 3.5 and 9.0 tons. Another two snakes of the same dimensions were made, one for stationary shots and one for decapitation by Schwarzenegger. The immense size of the mechanical snake meant that it did not fully fit onto the set, so only the front of it could be shown in the film. To create the scene at the Tree of Woe, the crew tethered live vultures to the branches, and created a mechanical bird for Schwarzenegger to bite. The dummy bird's feathers and wings were from a dead vulture, and its control mechanisms were routed inside the false tree. According to Sammon, "one of the greatest special effects in the film [was] Thulsa Doom's onscreen transformation into a giant snake". It involved footage of fake body parts, live and dummy snakes, miniatures, and other camera tricks combined into a flowing sequence with lap dissolve. After Jones was filmed in position, he was replaced by a hollow framework with a rubber mask that was pushed from behind by a snake head-shaped puppet to give the illusion of Doom's facial bones changing. The head was then replaced with a mechanical snake; as it moved outwards, a crew member pressed a