Mewtwo

"Fool, trying to stop our battle."~Mewtwo

Mewtwo is a psychic genetic Pokemon that resembled a Mew like ancestor of all Ancient Pokemon. Mewtwo can be considered evil, but more misunderstood because it was the way he was created. Mewtwo was created by Team Rocket by cloning DNA from a Mew fossil. (how they have the brains, we do not know.) It was Team Rocket's intention to create the most powerful Pokemon. However, Mewtwo was angered by the team as he heard that he was to be controlled by them, and in his fury, destroyed the lab where he was created with his intense psychic powers. Believing humans as oppressors of Pokemon, he vowed to exterminate humans and all Pokemon that sided with them, believing it to be his "purpose". He also wishes to exterminate Mew, as he believed he was vastly superior to his genetic counterpart.

Trivia

 * Different from many villains, he has no sense of happiness and has no evil laugh, but at the end, you can see a tiny smile on his face.