The fight scenes were filmed with live actors and then animation was created using that footage.
When Robin plays the flute with the two little monkeys in an attempt to take down the Joker, the tune is the opening part of the theme from Batman (1966).
The looks of Batman's villains are styled after those of Japanese historical characters, namely the feudal lords ('daimyo') whose province they are said to have taken over in this time-line:
- Penguin = Takeda Shingen.
- Poison Ivy = Uesugi Kenshin.
- Deathstroke = Date Masamune, well known for having an eye-patch.
- Two-Face = (a blend).
- Gorilla Grodd = Toyotomi Hideyoshi.
- Joker = Oda Nobunaga.
At one point Penguin yells "wind - forest - fire - bird", which is a twist on Takeda Shingen's personal motto "wind - forest - fire - mountain"). This was a reference to a Chinese text on warfare: "Be as swift as the wind, silent as the forest, fierce as fire, and as immovable as a mountain".
Monkeys, apes, chimpanzees and gorillas are sacred and worshiped by some Japanese cultures. They would regard Grodd as a deity before the other villains.