Robin Davies illustrations on the Ladybird book "A Trap For He-Man" still remain some of my favorite artwork featuring the Masters of the Universe cast. What I like about his early style is that he manages to capture the essence of the toyline, and combine it with the elements of the cartoon that we all know and love. This illustration of Skeletor is not over the top, not heavily detailed, but striking and powerful in its depiction of the villain. I especially like that we see Skeletor's sword, which is referred to as his "energy blade" in the story, held proudly by the character.
(click on the image to see it at full-size)