9. Iron Man Emerges
We gotta date back to the first MCU movie and pick out a key moment, one that launched a franchise.
The first Iron Man movie is incredibly well paced and has a very defined three act structure. And it takes a good long time to build up to the first time we see Iron Man. And that's why it works. You've sunk a good amount of time into watching Anthony Stark struggle and fight and scrape by on his wits and you've been watching him prepare for this very moment. We see brief shots of the suit as it's being built but then this moment comes.
The Ten Rings approach the door to the cell Stark is inside, they tense. And then something starts bashing at the door. It's scary, it's tense, and it makes Iron Man's first onscreen appearance feel rickety and sketchy and perfect. When he bursts through the door, the Marvel Cinematic Universe was born in the hum of transistors and the heat of a flamethrower.