Necromaniac: Schizophreniac 2 (1999)

Deranged and drug-addled misogynistic lunatic Harry Russo suffers from painful flashbacks concerning the abuse he suffered from his parents as a kid. Accompanied by his ventriloquist dummy pal Rubberneck, Russo embarks on a brutal psychotic spree in Las Vegas in which he rapes and murders old ladies, lesbian hitchhikers, and sleazy two-bit whores. Meanwhile, two scummy cops try to nab Russo.