Shadow Yosuke: Shirou and Izanagi had to face off against the boss alone, while it had a considerable advantage in speed and their types countered one another. At one point Shirou takes an attack strong enough to destroy the environment without any protection since Izanagi was protecting the others. He got right back up and kept fighting.
Shadow Chie: Yosuke tried a preemptive strike and when that failed worked in tandem with Shirou, as well as learning how to use his spells.
Shadow Yukiko: Not only did they have to face off against Shadow Yukiko, but its aide Charming Prince. Jiraiya was all but untouchable, so the shadow got clever by shooting Chie in the back with her weakness and then having her aide paralyze Yosuke and dropping a chandelier on him. Shirou summons Eligor to finish off Charming Prince, and Chie upgrades her regular spell to use Bufula and finish it. Before that, Yukiko herself shows her determination, cutting off Chie's apology to tell her and the others to run, fully intending to sacrifice herself to save them (though it doesn't come to that).
Chapter 23: Little Nanako calls out everyone for picking on Shirou. Considering she's normally a shy little girl, it was amazing.
Chapter 25: Kotomine Kirei during... all of it.
Taiga at the end of it for not only threatening Kirei's death with some rather interesting Noodle Implements, but actually convincing Kirei, one of the best executors during his tenure and Kiritsugu's equal in almost everything, that she could damn well do it given a chance.
Chapter 27: Kanji vs. the Biker Gang. Many were armed with weapons. He still kicked their asses. It's later mentioned he's been doing this since Middle School.
Not only does he kick their asses, he does so without ever needing to pause in his gait, barely even acknowledging their existences thanks to his experience as a fighter.
Chapter 31: The Persona Lilim becomes the epitome of "fight smarter, not harder" by turning the tide of the battle against Amorous Snake, more difficult here than in canon because it fights alongside with two Rainy Shadows, with one attack: Marin Karin, managing to Charm one of them into giving the coup de grāce to Amorous Snake and then instigated a Double Knockout between the remaining opponents.