Noun
The spirit each person is believed to have in attendance, according to certain religious or mythological traditions, which tries to negatively influence him, and is opposed by his good genius; loosely, someone who is a bad influence.
An intellectually brilliant person who excells at using his or her mental abilities for negative or harmful ends; especially a criminal mastermind .
Source: en.wiktionary.orgMy evil genius Procrastination has whispered me to tarry 'til a more convenient season. Mary Todd Lincoln
With the proper training, I could've been an evil genius. George Carlin
I wouldn't say jamie is an evil genius. I'm not sure he's evil and I'm not sure he's a genius. Adam Savage
Even if some "evil genius" were to be deceiving him, he would have to exist in order to be deceived. Source: Internet
Œnone, Phèdre's evil genius, persuades her mistress to tell Hippolyte of her incestuous passion, and incriminates the young prince on Thésée's unexpected return. Source: Internet
At one point Banks said: “I like to think I’m an evil genius with a white cap that controls the whole of western democracy but clearly that’s nonsense.” Source: Internet