Ygor seems more like a villain than a monster at first, using Frankenstein’s creation to wreak his revenge; the hunchbacked assistant somehow turned malign master. However, he remains…oddly difficult to kill, a trait that suggests he’s more than a simple maniac.
Dracula is clearly, patently, unarguably Lugosi’s most iconic role. On stage alone he played it over 10,000 times. However, onscreen he played the Count the same number of times he played Ygor. And Ygor, I think, might represent his finest screen acting. There’s a slyness and black humor to Ygor–”Er…they said…”–that conveys a subtlety that Lugosi sadly seldom proffered. Of course, it must be said that only with a (magnificent) ham like Lugosi could a crazy larger-than-life character like Ygor be considered subtle. But there it is.
Son of Frankenstein, I believe, is the only film where Lugosi gets the better of his rival Karloff (although Boris was clearly disenchanted with the direction the Monster was taking at this point, and it’s still a great performance).