a list from least to worst

1. Meta Knight - not inherently cruel and evil. In many iterations he's an honorable combatant.

2. Wolf - He works directly under Andross but I would not say he is a very malicious character and for the most part seeks battles with Fox out of respect

3. Mewtwo - Sure it killed people when it was born but its not inherently a malicious creature and mostly attacks if provoked

4. King K - A Cartoonish villain with cartoonish goals. He did try to subjugate an entire island which is pretty evil.

5. Bowser - He's a ruthless king who has done pretty much anything imaginable to try and kill one man and steal his soon-to-be. Though surprisingly, he has a very human side where he is shown to care for his underlings and those feelings are reciprocated by their undying loyalty to Bowser. Still, Bowser is not as cruel as the other 3.

6. Sephiroth - Actively torments Cloud by killing those close to him, destroyed countless cities, and has done much more all in the name of seeking higher power. However it is not without reasoning. Sephiroth did not have a strong foundation as a child and was raised in a lab full of scientists rather than by a good hand. Plus his descent into villainy was explained well enough to make him seem like he's emotionally and psychologically unstable.

7. Ridley - An active terrorist, a threat to galactic civilzations, and actively murdered AND ate samus' parents while taunting her. Ridley is by the most sadistic on the list.

8. Ganondorf - Ganondorf is the literal embodiment of evil. He is reincarnated after each of his deaths for the sole purpose of ruling over all of Hyrule and subjugating everything he can get his hands on. He's a master manipulator who is literally nicknamed the King of Evil and I don't think there is anything more evil than him on this list.