Firstly: the Arachne colouring is very nice, i think you could selout/aa better in the outlines though, as the head and legs are left slightly jaggedy, and i dont think you should let this stand when you've got some really good colouring going.
Secondleee: The weird monster thing seems very rushed and not much thought about the lineart and general structure. There's too much going on at once i think, with nothing general for the eye to gaze upon or from. Its body also seems too flat, there's possible pillowshading going on aswel. And the metal seems to be given a dented texture, rather than just a reflective surface. I suggest you research that a little more, as well as the flames, which at the moment looks like hair.
Hope that helps, keep it up.
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