Karl Denke

Killed and cannibalized poor travelers and homeless vagrants. Kept a ledger recording his murders with at least 31 names in it (including Vincenz Olivier, his only surviving victim), thus confirming at least 30 victims. But due to the massive amount of human remains found in his apartment, his kill count is suspected by many to exceed 42 victims. Committed suicide by hanging himself in his holding cell before he could be tried.