With the Spider-Man: Homecoming post-credits scenes causing as much buzz as the film itself, it's time we actually discuss one of the characters seemingly introduced in one of the two post-credits scenes. Of course we know about Adrian Toomes, a.k.a. Vulture, and Captain America, but just who is Homecoming's Mac Gargan? It turns out that Mac, who is introduced in the first post-credits scene with Vulture, is actually a very scary foe. If he does turn up again in the next Spider-Man film, Peter Parker should definitely take precautions to protect himself.
The movie's first post-credits scene makes it clear that Mac is a very intense character. He seems hell bent on finding out who Spider-Man really is and it sounds like he has a team of very shady guys waiting for the word to do his bidding. Well, it turns out that Mac's itch to find out Spider-Man's identity comes straight from the comics. According to Mac Gargan's Marvel Wiki entry, he was a private investigator hired by The Daily Bugle's J. Jonah Jameson to find out the true identity of Spider-Man.
Mac was unable to complete his task because Spider-Man's spider sense was always triggered and, as a result, he was able to elude Mac. Now, the backstory gets a little fuzzy here, but basically, J. Jonah Jameson agrees to help Mac by paying for him to be a part of an experiment which ultimately messes with his anatomy and essentially turns him into a human scorpion. It's bananas for sure, but hey, it's part of Spider-Man's history.
Unfortunately, the experiment and the process needed to keep Mac in working order as a human-scorpion hybrid caused him to lose his sanity. This led to him turning on J. Jonah Jameson and really stepping up his villain game. He basically sounds like an incredibly formidable foe and the fact that he has the lethal fighting and attack qualities of a scorpion while in a human body making him all the more formidable. Those fighting capabilities that make him such a big threat include superhuman strength, stamina, durability, and he has his own Scorpion sense, so Spider-Man isn't the only one who can tell when something's up.
While Mac as the Scorpion has existed for a long while in the Spider-Man comics — working with S.H.I.E.L.D. for a short time and crossing paths with various Avengers, going to Asgard, and even teaming up with other Spider-Man foes — the film makes it seem as if we are just at the beginning of his journey. Since Mac appears to be a human in the Homecoming post-credits scene, it looks like we might actually see him transform into one of Spider-Man's most fearsome opponents very soon.