As in the original TV episode "Elements of Harmony", each one of the Mane Six gets a moment to shine. Some get more than one. Several are exceptionally Awesome.
When Nightmare Moon collapses the ledge on which the Mane Six are standing, Applejack is the only one of the four non-Pegasi to save herself from a lethal plunge into the canyon. She does this by grabbing a root with her teeth on the way down. Then, realizing that Twilight Sparkle is in danger, she lets go of the root, makes a controlled slide down to the cliff edge, and holds onto Twilight long enough for Rainbow and Fluttershy to save her. And herself? She bounds down the vertical slope like a mountain goat, smiling happily at each leap.
In the next encounter, Applejack rides a Manticore rodeo-style. When it bucks her off, she calmly sails through the air, tags off to Rainbow Dash, and twists like a cat to make a perfect landing.
Nightmare Moon Lampshades this by remembering that her clan was known for being tough and fearless warriors over a thousand years ago and that they evidently haven't changed much.
Nightmare Moon initially judges Fluttershy to be a "coward." ThenFluttershy stands up to that same manticore and befriends it in a matter of seconds, against Nightmare Moon's direct Mind Manipulation (Nightmare Moon had infiltrated the creature's nervous system and was sending electrical impulses directly to its brain centers). After that, Luna refers to her as the "mind-witch" in her own thoughts.
At first Nightmare Moon assumes that PinkiePie is just plain "simple". Then Pinkie dispels one of her strongest and most dangerous area enchantments — a combined Illusion, Fear and Animate Object spell — apparently by just laughing at it, but Luna can tell that Pinkie has actually performed a powerful reality warping. In-story the effects are described as the Anti-Magic equivalent of a Fantastic Nuke!