Herbert William Mullin was an American serial killer born on April 18, 1947 who operated in Santa Cruz, CA. 
Mullin was serving life in prison for 13 murders which he says he committed to prevent further natural disasters.  Mullin died of natural causes on August 18, 2022.
 
8 1/2" x 11" on which he has calculated the amount of days, weeks, months, seasons, and years he had been alive at the time he put this together. Includes an original drawing below his calculations which Mullin has called, "Full Moon."
Hand signed in full, Herbert William Mullin.