noun

a person who commits profoundly immoral and wicked deeds.

his concept of justice demanded vengeance against evildoers

wrongdoer,transgressor,criminal,delinquent,offender,villain,black hat,malefactor,reprobate,scoundrel,rogue,sinner,sinful person,wicked person,evil person,bad person,baddie,bad guy,crook,wrong ‘un,ne’er-do-well,nasty piece of work,ratbag,scumbag,bad egg,crim,malfeasant,misfeasor,infractor,miscreant,knave,blackguard,varlet,trespasser