Obviously there is no right answer, but there are a lot of people (almost all men) who have deeply malign intent, poor impulse control and very low empathy.
Most of them have little power beyond their immediate circle (but I feel tremendous sympathy for those unable to escape that circle). Men who abuse their partners or kids. Horrible, angry, disgusting men.
Some of them have obtained power in their jobs or politically, and can exert their making influence over far more people than way. Some are obviously able to exert it over millions.
I think in this group there are people like Trump, Putin, Netanyahu, Kim Jong Un. The scale of what they've actually done with their power is one thing, but I think what unites them is that, unchecked, they'd all be as bad as the worst one is in reality. Trump would send people to re-education camps and execute people on the spot like Kim does if he could. Luckily the USA legal system won't let him.
And then there are men who acquire enormous influence and power through wealth, and use it for evil. Peter Thiel, Elon Musk, the AI people.
They're all as evil as each other. They all have evil in common.