To kill is in the mafia life but some mobsters had a body count hights than other,I tried to do a list.

Giovanni Brusca (sicilian) 200+ (even him don't remember the real number)
Maurizio Avola (sicilian) 80
Roy Demeo (gambino) 70 (maybe)
John "Sonny" Francese (colombo) 60+
Benjamin "Lefty" Ruggiero (bonanno) 20 +
Salvatore "Sammy the Bull" Gravano (gambino) 19
Phillip "Crazy Phil" Leonetti (Philly) 10