One of the big surprises at the end of Spider-Man: Homecoming was the introduction of Mac Gargan, aka Scorpion, as played by Better Call Saul actor Michael Mando.
After several failed attempts, Gargan undergoes a procedure which, naturally, goes awry and turns him into the villain Scorpion.
Mac Gargan kind of goes a little bit insane, and there’s also this other story where he becomes Venom as well.
And it was pretty disappointing when the character didn’t show up in Spider-Man: Far From Home.