Daemon is the antagonist of the story, so his design had to be able to clearly communicate his position.
Initially I was inspired by the Japanese mythological figure of the Oni, but the armor was too confusing. To overcome this problem I tried to decrease the inspiration linked to Japan, trying to focus more on the demonic elements, thus managing to further improve the sketch.
Despite this, the design still didn't seem complete to me, so, to underline the industrial element of the design, I added a furnace on the belly keeping the mask and the belt as elements related to the Oni figure.
To underline his demonic nature I created his shoulder straps through the use of huge skulls with only one horn, and as a face, to underline his nature linked to the element of fire, a huge purple blaze. The last one on the right is the definitive one.