YMMV / The Adventures of Batman & Robin E13 "Showdown"

• Aluminum Christmas Trees: The first zeppelin (rigid airship) was not designed by Ferdinand von Zeppelin until 1874 and not built until 1893, but the first powered airship was developed in Paris by Henri Giffard in 1852, floated with hydrogen and propelled by steam. Helium was discovered as an element present in the sun's combustion in 1868, but the process of synthesizing it on Earth was not discovered until the 1890s, which meant hydrogen continued to be used in airships until then (and in German airships until the 1950s, because of American embargoes during the World Wars).
• Moral Event Horizon: Arkady Duvall has already crossed it according to Jonah Hex who has tracked him across twelve states "on account of what he had done to a girl back east" and as if that wasn't enough a barmaid at the beginning of the story tells Hex "He hurt one of my girls real bad." They don't go into detail, but he at the very least violently assaulted them. When the man appears in person, he's whipping one of Ra's workman for slacking, when all the guy was doing was trying to pick up something he'd dropped. When Hex is caught spying on them, Duvall orders the workers to lower him head first into a vat of molten lead, sealing him as a murderer along with abuser.
• Spiritual Successor: Of an Elseworld story, Batman: Master of the Future, which had a similar sword-wielding European madman on a metal airship during the late 1800s.

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