The Return of Hydro-Man: Part 1 - S5-E7
Other mistake: When Spider-Man catches up to Mary Jane and Hydro-Man at the foundry, he webs up Hydro-Man's left wrist. When the shot changes to Spider-Man landing, he is not holding onto the web-line. When the shot changes back to Hydro-Man, his arm his pulled with the web-line remaining taut, even though Spider-Man is not holding the web. If Hydro-Man was moving his arm on his own, then the web-line would be slack.
The Return of Hydro-Man: Part 1 - S5-E7
Other mistake: When Spider-Man breaks the chain off the steering wheel of the boat, several of the links on the back loop of the chain break off, which would be impossible since he broke the chain at the front.
Answer: In the comics, Hobgoblin's true identity was kept a mystery for a long time intentionally and while many fans deduced it was Kingsley, and creator Roger Stern was leaning that way, Stern left the series in 1984. In 1987 Hobgoblin's identity was revealed to be Ned Leeds and then Macendale became Hobgoblin. It wasn't until 1997 that Sterns wrote the mini-series "Hobgoblin Lives" and retconned Kingsley as the original Hobgoblin.
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