37. Skeletor, 'He-Man and the Masters of the Universe'
The action cartoons of the 1980s were full of memorable villains, which made good financial sense: Many were glorified commercials for toy companies, and kids needed figures for their heroes to fight, right? But of all the big names — Cobra Commander, Megatron, Hordak, Mumm-Ra, the Shredder, the Misfits — Skeletor stands out from the pack. His skull-faced character design is a perfect encapsulation of what a "bad guy" would look like to a child, and that imperious cackling voice (courtesy of actor Alan Oppenheimer) is the sonic antithesis of He-Man's heroic "By the power of Greyskull" battle cry. And most importantly for young viewers, he never wins.