The Evil Dr. Edlemann
His blood gets contaminated with Dracula's, right? So in a sense, it makes him part Dracula. His Dracula half is kind of like his Hyde. He casts no reflection in the mirror when he becomes the monster. He's able to overpower and ferociously kill Siegfried in seconds.
But bullets can kill him? If his evil half is his Dracula half, then why would bullets stop him? It didn't make any sense to me. I liked Dr. Edlemann in the movie. He was a good man that wanted to help people. He even wanted to help Frankenstein's Monster. I felt bad when Dr. Edlemann became a monster and ended up dead. I thought that was stupid. I wish Dr. Edlemann never became a monster and lived in the end. Dracula should've been the villain in the end instead of Dr. Edlemann. Dracula should've killed people. Dracula should've been the one the villagers were after in the end. Dracula should've forced Dr. Edlemann to bring the Monster back. If it was up to me, I would've had Dracula kill Siegfried and others. Then in the end, Talbot and Dr. Edlemann could've tried to stop him. Dracula could've only been there to have the good doctor revive the Monster all along. He was going to leave with Dr. Edlemann's lovely nurse and take the Monster with him. He could've been overpowering the mortal Talbot and the doctor could've revived the Monster to wake up and help him. In the end, the Frankenstein Monster could've had a fight with Dracula. Unfortunately, Dracula and the Monster didn't meet as enemies until the grade Z movie Dracula VS Frankenstein.