Batman: Arkham Knight/Nightmare Fuel


 * Almost the entirety of "The Perfect Crime". Professor Pyg, already a disturbing and unsettling character in the comics, is his own flavor of frightening, with a ghastly pig mask, operatic motifs and an obsession with completely warped standards of beauty. Like in the comics, Pyg distinguishes himself most from other Batman villains as an example of much more "clinical" insanity, without any Phlebotinum required.
 * This is best displayed in his Dollotrons - Pyg uses chemicals and surgical treatments to brutally destroy any semblance of identity, lobotomizing his victims into a state of servitude where they can't think or feel anything. This leaves them irreparably scarred, physically and mentally - and that assumes they survive the process, as Pyg kills the people he can't "fix" and discards them like trash.
 * The Dollotrons are highly resistant to pain and are unable to resist Professor Pyg's command; by using Detective Mode as you fight them, you can see they're clearly terrified out of their minds and powerless to stop themselves. Worse yet, only complete unconsciousness can stop them - Batman explicitly calls it a Fate Worse Than Death.
 * Remember the sneak peek of Killer Croc that you got during ? He now resembles a hideous, miniaturized kaiju more than anything remotely human, and you get to meet him in the flesh in "Beneath the Surface".