Atheism is more evil than satanism both in the moral and realistic sense. Morally, atheism decides its own values and principles or derives its values arbitrarily from others and that makes it dangerous. Realistically, atheism has, hand in hand with other ideologies, been one of the largest destructive forces in the world. Demonstrated in facist and totalitarian regimes, most notably in Stalinist or Maoist communism or Nazism. Those who question this ignore the communist manifesto clearly stating the scourge of religion as well as Hitler's persecution of not only Jews, although most notably, but also of Christians within his regime.
I would give you guys Stalin and Zedong. But Hitler was definitely Christian. If not, he used the religion as a tool. As atheists Stalin and Zedong don't have any justification for what they did to the religious. Pol pot was a Buddhist I think.
Stalin and Mao did despicable things in the name their ideology - Communism. Just as Islam, Judaism and Christianity have done. Atheism is not an ideology, it is a lack of belief in God, nor more no less. It makes no sense to say people would do bad things in the name of atheism. That's like saying they would do bad things because they don't believe in unicorns, or bacteria.
I love how you use pictures of Stalin, Mao and such just because their atheist them being atheist has nothing to do with what they did [Being fake totalitarian and ruining the image of Communism and committing horrific acts].