Two previous Penguin actors are referenced in shop signs:
- "Burgess Jewelry Design and Repair" is named after Burgess Meredith who played the Penguin in Batman (1966) and its spin-off movies
- "Danny's Roofing Corp" is named after Danny DeVito who played the Penguin in Batman Returns (1992).
As Oz inspects Alberto's phone, he opens up its calendar, which includes a meeting with a group called, "Gotham Knights."
It is revealed that the Penguin suffers from a birth defect called club foot, which is a deformity that gives his foot a flipper-like appearance as well as his trademark penguin waddle.
Oz recruits Victor from Crown Point, one of Gotham's most dangerous areas. This neighborhood is infamous in DC Comics for being the worst part of the city, a place where even the police avoid going.
Penguin catches Victor trying to steal his car tires, and takes him in as a protege. This is almost exactly how Batman met the second Robin, Jason Todd, in the comics.