The “winner” is Mao. Stalin and Hitler round out the top 3.
It’s always good on occasion to remember how governments and societies can go collectively insane. When the ends justify the means for a large group of people in a community the rest of the community had better be very wary, and should vigilantly counter this kind of thinking.
Most (probably all) of the men featured in the graphic thought they were doing the right thing, bettering humanity. That is how they justified their human cull. Not that the bloodshed was the goal. It wasn’t. But it was a price they were willing to pay to achieve their collectivist visions.