Gastly is the second Pokemon to speak human language in the show, after Meowth.
This is the first episode in the series to make some reference to real-world religion showing examples such as talismans and a cross.
The festival is the first time Misty is seen with her hair down.
James mentions the F.B.I when he encounters Officer Jenny.
This is the first episode to show a real ghost, as the true spirit of the Maiden speaks with Gastly near the end.