I am a novice at this and no sculptor so this figure is mainly a 'spare parts' custom. The idea was to make an Arc Trooper with a twist; the head! I'll get to that part. I used the tip of softening figures from YouTube using hot water/hair dryer. I placed the legs of the black and the White Darth Vader in a bowl of hot water for approx. 10 seconds, then I a pair of pliers to firmly but also gently pull their lower legs out of their thighs. While it was still soft, I removed the knee joint from the boots and let the harden by leaving them to cool for about 5 minutes. After that I re-softened the white boot and inserted the cooled black knee joint into the boot part. The black Darth Vader was thermal softened and I pull at an on the waist and lower body to separate the parts. The Damian figure was thermal soften to remove the arms and head. I then used a remel to cut the torso of the Damian figure separating it from the legs. I smoothed the edges and drilled a hole in the centre of the under part of the torso widening it to approx. 0.5cm in diameter. I thermal softened the torso and pushed the lower waist into the torso. I removed the arms from scuba trooper by cracking open the seam of the torso. I used a dremel to shape the pins of the shoulder joint to fit into the shoulder socket of the Damian torso by thermal softening. I then removed the head from Northstar marvel universe figure as it fitted the helmet and the torso.