Complete Monster/Mass Effect

""Tell your assassin to aim for her head, because she doesn't have a heart!""
 * Saren Arterius. Let it be known that he was a Complete Monster before, that he seemed to enjoy going Knight Templar on targets and even innocent civilians. His mass-murder on Eden Prime was only the most extreme act of calumny on his part.
 * Dr. Saleon, a salarian geneticist who sold black market body parts and organs. How did he get these organs? He hired people off the street and grew the organs inside of them, making them living test tubes. If the organ didn't work out, he would leave it inside of the person.
 * And then you track that motherfucker down in the game and find several of his test subjects in a horrible state of being.
 * Oh, and if a Paragon Shepard convinces Garrus to arrest him instead of just killing him, he responds to this generous act of mercy by trying to kill them with a dingy rifle. So not only is he a monster, he's Too Dumb to Live to boot.
 * Immoral scientists always seem to be these in the Mass Effect universe.
 * There's also, the from the first game. In the sequel, she's left politics and is now a Properly Paranoid Corrupt Corporate Executive who orders her Mecha-Mooks to gun down her own employees out of paranoia. Even Paragon Shepard is glad to see
 * It's also heavily implied that if one her employees leave before the contract expires, she has them murdered.
 * She ordered one of her soldiers to hunt Shepard's team down, but he was Genre Savvy enough to refuse. Once she convinced him otherwise, she randomly killed him and threw into a hole that led to the bottom floor.
 * One of the workers you end up saving has this to say: