Imperfect Cell was probably my all-time favorite DBZ villain. His voice, his insect-like origins and earlier behaviors, and Bruce Faulconer's hauntingly slow, industrial music will stick with me forever. He was a different type of villain, opting to disturbingly drain his victims of their lives rather than merely blasting them into oblivion. I didn't really care for Cell as a villain once he started "perfecting" himself. He was just a regular jerk. In this incarnation, we was a literal monster.
This drawing captures those feelings wonderfully. The way you used the contrast of his dark, staggeringly tall figure against a bright, sunny day is an excellent way of conveying his terror. I will say that his upper torso seems a bit too wide, and the positioning of his mouth seems slightly off. However, the coloring and shading is especially stylistic and admirable. Great work, keep it up!