Some honorable (or is that DIShonorable?) mentions.
Eve. Off playing with some snake, ultimately responsible for getting us kicked out of the garden of Eden, mother of the first documented murderer...
Kaiser Wilhelm: Who sent Lenin to Moscow to stir up trouble and mess up the Russian war effort, leading to the October Revolution, the murder of his own cousin and his family, and eventually to the Soviet Union, the Cold War, Uranium One, and the Mueller Investigation.
Hillary Clinton. Long seeking political power, involved in shady cattle futures trading, shady bank and real estate deals, enabled molestation of other women in her desire to retain her ticket to power, illegally collected raw FBI data on ranking political opponents and others (yes the FBI corruption has been going on THAT long), possibly implicated in the curious demise of numerous former colleagues and associates, architect of an early form of Obamacare, complicit in the questionable presence and likely distribution of classified (to Above Top Secret) materials through intent or careless handling, implicated in Benghazi incident through lack of security, party to a Foundation which skimmed (failed to distribute) massive disaster relief resources from desperate third world people in Haiti, likely profited from the sale of strategic assets to foreign powers (real Russian collusion), etc.
Friedrich Engels one of the creators of what they called "scientific socialism". (With Karl Marx)
Alfred Kinsey, whose research into sexual behaviour went beyond the pale, may have been fraudulent, but set the stage for the sexual revolution, and not just heterosexual, and sometimes pedophillic in nature. The downside of all of this is that harnessing the natural tendencies for people to become involved in an instinctive behaviour with just a little prodding (no pun intended), it is easy to get an entire society so wrapped up in sexual matters they not only ignore other things in their world, they start getting confused, leading ultimately to concepts like 52 genders, etc.
Timothy Leary: Turn on tune in drop out (later used by Jerry Rubin as well), did much to promote the use of hallucinogenic drugs ostensibly for research and under controlled conditions at first, but in reality pushed drug use into the mainstream. What had been the provenance of jazz musicians and drug addicts became less stigmatized, more commonplace, and now, widespread, accounting for more deaths a year than car accidents.
Charles Darwin, who provided the basis by which countless atrocities have been justified, from slavery, economic exploitation, to attempted genocide, namely that there are less advanced and developed forms of human, less human, sub human, and that they are lower on the evolutionary scale. Without the concept that people are created in the image of their Creator and that all are equal before Him, just about anything can be justified or rationalized, and has been.
Walter Cronkite: Who, with complete gravitas, convinced America that the Tet Offensive (and subsequent defeat of the Viet Cong throughout South Vietnam) was a loss, militarily, and that the war could not be won. (See also, Jane Fonda, Joseph Goebbels, Leni Riefenstahl)