Katniss, after attempting to save Gale from being whipped by a Peacekeeper Commander Thread, looks the Thread in the eye (after being beaten herself), and only says to him, "Go ahead."
And then Haymitch and Peeta put themselves between Thread and Katniss, and Haymitch talks Thread down, pointing out that he's about to kill three Victors and the Capitol will not like it.
In the aftermath, Prim gets to show her stuff as she calmly takes over Gale's care after her mother's hands are shaking too much to load a syringe. Katniss is shocked to see how far she's come from the terrified girl who couldn't keep her shirt tucked in.
When each Tribute is asked to "demonstrate their preferred skill" before potential Capitol backers, Peeta goes in before Katniss. When she enters the training room, he gives her a brief look. Then she sees that right before the backers he's used his skill at painting to draw an enormous tribute to Rue. What's more, Peeta made the painting within ten minutes.
Katniss demonstrating her archery skills in the training center. She starts off with only Mags watching her, and when she's killed all the targets, she looks and sees all of the tributes genuinely applauding her.
And then her individual trial, where rather than demonstrate her archery again, she hangs Seneca Crane in effigy. That is, her special talent is beating these guys.
Johanna Mason having the guts to say exactly what she thinks about the Capitol when she's forced back into the Games:
"Why yes, I'm angry. You know, I'm getting totally screwed over, here. The deal was that if I won the Hunger Games, I'd get to live the rest of my life in peace. But now, you want to kill me again. Well, you know what? F*** THAT!"
Followed by a massive Cluster F-Bomb that gets just bleeped out enough to prevent the film from getting an R rating.
Followed by another moment when Johanna calls Snow out... on national television... from within the Arena.
HOW DOES THAT SOUND, SNOW?!! WHY DON'T WE SET YOUR BACKYARD ON FIRE!! YOU CAN'T PUT EVERYONE IN HERE!!
Especially gutsy because Johanna has to know that even if she makes it out of the Arena alive, Snow will probably make her pay for her words.
The 24 tributes all holding hands in direct defiance of the Capitol during Caesar Flickerman's show. Made even more awesome when they try turning the lights out, and the very last one to go is the screen behind the tributes, silhouetting them.
Cinna's Mockingjay wedding dress for which he pays with his life.
Katniss and Finnick's first battle at the Cornucopia. Made better by the fact that it's not really a battle - Katniss points an arrow at Finnick, and he calmly shows her Haymitch's bangle:
"Good thing we're allies, right?"''
Peeta also gets one at the Bloodbath. Mags finds him wrestling with the male from District 9. By the time Finnick and Katniss get to his vicinity, it seems Peeta has been overpowered. Finnick swims over, only to find that Peeta was able to drown the other tribute on his own.
Listed under the funny example as well, but Peeta dropping the Baby Bomb. It was his last-ditch effort to derail the games, and based on the horrified reaction from the audience it almost worked.
Mags' Heroic Sacrifice to save Finnick, Katniss and Peeta. And volunteering for the Quarter Quell to save Annie.
In the latter moment, you can clearly see the moment when she decides that no, she is not going to let this happen to Annie again, as she shakes her head and sticks her hand up, pointing to herself with angry defiance. Mags has mentored tributes (and watched most of them die) for her entire adult life, and now she's doing what she probably wanted to do all those years: going to die in their place. That is what being a Mama Bear is all about.
The moment when Katniss destroys the dome by shooting the arrow with the wire tied around it as the lightning bolt strikes it. The set-up and execution nails it.
A mix somewhat of Fridge Brilliance and Awesome, but in the book, Katniss has this line when she sees all the water: "This is no place for a girl on fire." After she brings down the dome, she is surrounded by flames. Girl on fire, indeed.
The film's final shot, with Jennifer Lawrence giving a masterpiece of acting as Katniss weeps over learning about District 12's destruction, before her face changes to steely determination to make the Capitol pay.
It's more behind the scenes than anything else, and Katniss only learns of it towards the end. But Plutarch'sentire gambit is nothing to scoff at. Not only does he become Head Gamemaster and get on President Snow's good graces, but he manages to outwit Snow at his own game and get away with it. In fact, if not for him, Katniss and Peeta would have been killed right on the spot.