More then you can count
Yes, the Nazis did extract the gold fillings fromthe teeth of Jews without using pain killers. Bt it did not matter about the pain killers becasue they did it after they had murdered the Jews.
There are many theories as to why serial killers appear
The Postcard Killers has 432 pages.
Killers of the Dawn has 206 pages.
Japan gave the serial killers hitory with 12 serial killers to date.
The Real Cool Killers has 159 pages.
I could find no serial killers from Coweta, KY.
Below is a link to a complete list of serial killers.
The vast amout of killers have killed only once.
There are too many names to list here. Long lists of their names were compiled by their killers. The lists have been preserved, and may be viewed at the Yad Vashem memorial to their memories, in Israel.
One - "The Killers". It was his last film.
Not many, don't worry.