Other mistake: Spider-Man is shown web-slinging past several glass buildings, but he does not cast a reflection in any of them. (00:00:10)
The Alien Costume: Part 1 - S1-E8
Other mistake: After tricking police by disguising himself as a policeman, Spider-Man changes his clothes in the middle of traffic with numerous people around but somehow nobody notices this.
Other mistake: Despite being Shield agents the guys shown in the target practice room wear the same uniforms as the guards working for The Kingpin.
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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