There was an obscure DC Comics villain called The Archer, but he was a foe of Superman and the producers of the Batman TV show were apparently unaware of his existence. Unlike this Archer (and the more famous character Green Arrow), the Superman villain did not employ trick arrows until long after the television series ended.
This is the second time Dick Grayson is seen playing the piano, the first being The Joker Is Wild (1966). Likewise, the painting of Bruce Wayne's great-grandfather, first shown in Fine Finny Fiends (1966), is shown to conceal a wall safe.
The sound-effects cards are written in faux Old English; e.g., "Thwacke!", "Wham-eth!", etc.
The truck that Maid Marilyn drives is an International Harvester Sightliner.
At the end of the episode, the narrator previews the Batboat, Batcopter, and Batcycle, telling viewers to tune in for future episodes to see them in action. All three vehicles were designed and built for the 1966 Batman movie that premiered in theaters between the first and second seasons and were then used in the series.