While the beginning of Episode 3 takes place long before the main story, we see a Badass Normal and his companions infiltrating the palace, before he successfully assassinates the Emperor. He ends up dying from his wounds, but still.
As Rijin leads the main characters out of the forest, their ambushed by an army of Bakenezumi. Rijin takes them all out by using his psychic powers that resembles a grim reaper. Needless to say, it has to be seen to be believed.
Satoru taking out an entire network of installments belonging to the hostile Ground Spider colony... by tossing a single blue torch.
Saki gives Satoru's Juryoku back. Cue a non-stop chain of Curb-Stomp Battles against the Tarantula colony.
Saki suiting up and going stealth to save Shun single-handedly in Episode 9. While it remains to be seen whether her mission will be successful, getting that far undetected past high security as a 14 year-old girl is impressive.
In episode 10, we witness Saki facing off against a Fujoneko monster. Even if she used Shun's collar to defend herself, seeing her take down the monster with her Cantus is definitely a sweet, if trippy, moment.
Subaru saving Shun and Saki when another Fujoneko ambushes the two. Doubles as a Tear Jerker since Subaru gets killed.
Tomiko gets her Big Damn Heroes moment in Episode 14, when she sticks up for Saki and calls them out for driving out Mamoru and Maria from the village.
Saki herself gets another moment of awesome during the interrogation. Remaining calm and patient, she tells the not-so friendly Board members truthfully what happened to Mamoru, before revealing her knowledge of what they did to him.
Episode 18 shows Shisei and Hino using their canti to utterly crush Yakomaru's invading army when they raid Kamisu 66's Summer Festival. From changing the wind's direction and mind controlling the soldiers to triggering a soldier's TNT, containing the explosion, AND using that explosion as a beam weapon, they show why they are so trusted by the Ethics Committee (even if Hino died in the battle).
Episode 19: Upon arriving at the hospital's dock, Satoru realizes that Bakenezumi soldiers have hidden themselves in the rice fields preparing for an ambush. Saki, Satoru, and Fujita promptly show how the Kill It with Fire trope is done, wiping out most of Yakomaru's ambush team. And it's glorious.
Satoru himself in this episode (and the next), performed magnificently. This guy needs a trophy for thinking on his feet while everyone else (save Saki, just barely) were ready to piss themselves in terror. This becomes more prominent when you notice that he was usually the first one to even realize they're in deep shit. Saki herself comes in close second.
Episode 25: Saki's plan and Kiromaru's heroic sacrifice to stop the Akki works.