The first time we get to see the Dominator's Destroy Decomposer mode in action in episode 3. As if this gun couldn't possibly be cool enough, it can also vaporize mechanical enemies every bit as effectively as it does humans.
In episode 5, when the Internet Mimic serial killer is cornered by our heroes, he activates a giant holographic disruption to Mind Screw them and get out of there. In response, Masaoka whips out the bottle of alcohol he'd had on him and concocts a Booze Flamethrower to set off the fire-extinguishing sprinklers, deactivating the holograms.
Tsunemori telling off, and effectively shutting up Ginoza in episode 9.
In episode 10 Masaoka was finally fed up with Ginoza picking on Akane. As a result the inspector was given a free flying lesson.
The entire battle between Kogami and Toyohisa Senguji in episodes 10 and 11. First taking out one of the robot dogs using the Spikes Of Doom on the ceiling, and then retrieving his Dominator and using its Destroy Decomposer mode to eliminate the other dog. Finally ending with Kogami pulling a move that would make Solid Snake proud: hiding in a barrel and rolling down a ramp, prompting Toyohisa to check the top of the ramp, followed by Kogami popping out of the barrel and blasting Toyohisa with the Eliminator mode.
(doubles as a Heartwarming Moment) His first priority afterwards? Telling Yuki to get out of there and seek therapy for what she's seen, despite the fact that he's been shot a number of times. The man's a damn fine detective.
And when he wakes up, he immediately tries to go after Tsunemori, despite having near fatal gunshot wounds. Masaoka has to headbutt him to get him to stop.
So, Akane feels guilty after Spooky Boogie died while assisting the Bureau. In most other shows, it would take at least one episode of dealing with and overcoming it, with lots of drama. Here Kougami basically solved it with just three questions. An awesome feat.
And in episode 13, she quickly bounces back after Yuki's death, resolving to hunt down Makashima.
At the end of episode 14, Makishima effortlessly takes down a trio of thugs alone and unarmed.
Episode 16. Akane knocking Makishima out with a helmet.
Even better when you consider the implications behind it: Makishima dismissed Akane for failing his "test". He's also the one responsible for the existence of the helmets. That's right folks, he was beaten with Poetic Irony. What really makes the scene is the fact that the injured Kogami tells Akane to kill Makishima. She has the helmet over her head, she's remembering Yuki and how Makishima killed her, and she's clearly enraged... and then she drops the helmet, pulls out her handcuffs, and tells Makishima (who may or may not even be conscious) that he's under arrest.
Shusei kicking the asses of three of Makishima's henchmen with ease. Too bad he got killed afterwards by Jousei.
Makishima throwing the offer to become part of Sybil back in Jousei's face, and proceeding to rip him apart with his bare hands. And a hardcover book.
Episode 18 has Akane saving Kogami from being killed by the chief by shooting him with her Dominator like she did in the first episode.
And Episode 20 has Akane give the Sibyl System an ultimatum: They spare Kogami's life in exchange for her bringing Makishima in alive. When the system shows signs of not agreeing, she says that if it doesn't, she will do nothing while Makishima dies, even threatening to kill him herself if need be. To cap it off, she tells the system that if it refuses to kill her like it did Kagari and find a new pawn, going so far as to hold the barrel of the Dominator to her chest.
It doesn't stop there. She correctly profiles Kougami's path through the house and discovers his message by herself. Those Sherlock Scan lessons from Professor Saiga really paid off.
Episode 21 has Masaoka fight Makishima and manage to get him in a hold. He probably would have beat Makishima, if Makishima hadn't tossed dynamite at a trapped Ginoza. Sadly, this leads to Masaoka pulling a Heroic Sacrifice to save his son...but he still kicked Makishima's ass.
In the finale, Makishima is on the verge of escaping in a stolen truck, until Akane, who is hanging for dear life on the exterior, manages to use the last shot in Kougami's revolver to blow out one of the tires.
The final episode has Shinya finally killing Makishima.
In the final episode, Akane tells the Sibyl System that humanity will outgrow the need for such a system and that people will always strive to make the world a better place. To see that Akane still has her ideals after everything that happened is amazing.
Also from the final episode, Akane finally manages to express the core of her idealism: "The law doesn't protect people. People protect the law."
A small one but the new Inspector? It's Mika Shimotsuki from the Rikako Oryo case. After losing her friends, she's managed to keep her Psycho Pass healthy enough to join the CID as minor.