The Animatrix/Nightmare Fuel


 * The two-part story of the machine/human war - The Second Renaissance - is particularly brutal. A humanoid android "woman" is beaten to death by a crowd of human men. She is beaten, stripped of her clothes, and eventually her synthetic skin revealing her robot body. All the while she screams, her voice becoming more machinelike with each blow.
 * What makes that scene a lot worse is what the woman is screaming. "I'm REAL!"
 * The scene of the human woman having her head crushed by her once-peaceful robot servant.
 * There was the battle scene where a soldier has the front of his mecha unit ripped open by a Sentinel robot, which coils its tentacles around his torso and rips him out, leaving his arms and legs strapped into the mecha. The worst part is way the man is screaming "God help me! GOD HELP ME!!!" right up to the last moment.
 * The last scenes where people are being surgically operated and experimented on by machines while awake.
 * Real-life It Gets Worse: the kind of brain surgery that the machines do during that sequence? Something similar is done to remove blood clots, protruding bone, and aneurysms from the brainpan, and just like what the machines were doing, the patient has to be awake for the procedure.
 * All the disturbing imagery in The Second Renaissance is made even worse when you learn that most of it is based on real-life occurrences. For instance, there is a sequence where a human soldier shoots a restrained and helpless robot in the head point-blank with a pistol. Sound familiar?
 * One the worst parts was that - judging by the obvious bias in the supposed "historical record" - the Machines are just as prone to arrogance, self-righteousness, and all the other human failings as we are. It's like the human race quadrupled in capacity for terror, Three Laws be damned! The other option is that preserving the human race in the pods is actually the Machines' idea of keeping the human race safe...
 * There was a short about a track-star who almost, almost managed to break out of the Matrix... But at the last moment his muscles snapped, confining him to a wheelchair in a catatonic state. We're never told if the Agents had something to do with it (they were aware of him) or if it was simple human failing, but it was possibly the most haunting entry in the anthology, and the realistic-yet-exaggerated animation didn't help.