By the end of chapter 9, Twilight, Pinkie Pie, Applejack, Rarity, the ponies from Mirage squadron, the Wonderbolts and Cutie Mark Crusaders all sing "Gotta Stay Fly" from Ace Combat: Assault Horizon (with slightly changed lyrics) and the entire ballroom cheers on them and applauds their performance.
Rainbow Dash performs a Sonic Rainboom to break inside The Burning Talon in chapter 10.
Scootaloo and Sweetie Belle get one in chapter 11. They use a home-built catapult to help defend Ponyville from the griffin attack.
Medley's Foe-Tossing Charge in which she defeats two griffins that held Rainbow Dash captive.
The way Rainbow Dash rejoins her fellow fliers by the end of chapter 12.
Rainbow Dash: Iím sorry to keep you waiting, girls. Letís get the show on the road!
Garuda team's Big Damn Heroes moment in chapter 13. Heralded by this quote:
Talisman: We bring the fires of liberation.
One of the griffins bombing Stalliongrad is disposed of rather nicely. As Derpy closes in, he drops his bomb and tries to bug out... only for Derpy to catch up with him and send him tumbling through the air, out of control. She then knocks him straight into the ground, and into the blast of his own bomb. Boom.
There's one subtle awesome moment for Derpy and Medley in chapter 14. Using a broken piece of turret, Medley throws it at a griffon as a distraction before Derpy dive-attacks him and pushes the enemy toward Medley for an uppercut to the beak.
As reported by Flare Star in chapter 15, Blueberry fought against four griffins all by herself and even managed to kill one before being cut down herself. Talk about a Dying Moment of Awesome.
The whole chapter 17 can be seen as this for the ponies. Not only Canterlot is liberated, the ponies in other cities decide to lead their own counter-strikes, driving the invaders away.
Fluttershy vs. Night Raven. What seemed like a cruel No-Holds-Barred Beatdown at first, with Fluttershy being the victim, she managed to turn the tables after Night Raven revealed to her how much of a Blood Knight he is. The fight then ends with Fluttershy beating the crap out of Night Raven, then killing him via Neck Snap.
Most of the stuff Firefly does in chapter 19.
Zeakros sentencing Red Cyclone to die inside the collapsing Fortress Intimidation after his crimes are revealed to the griffins.
The final battle between Rainbow Dash and Gilda in chapter 20. Especially how Rainbow Dash turns her foe's Break Them by Talking tactic right back on her.
Derpy uses a guided penetration bomb to blow up one of the Exile battleships. Her sight is no hindrance at all. Plus, she follows the bomb drop with a great Pre-Mortem One-Liner:
Derpy: Here's a special delivery!
Even better, the other ponies defending Fillydelphia follow Derpy's example and attack with their own bombs...and sink the entire Exile fleet! The only things left floating are the lifeboats from the wrecked enemy ships.
By the end of the chapter, the Exiles attempt to nuke Fillydelphia using a cruise missile fired from Scinfaxi. Everypony pretty much gives up hope, but not Rainbow Dash, oh no! She channels her inner Colonel Bishop by telling Tornado Swirl to give his mounted machine guns to her, straps them to her body, then goes after the missile and shoots it down seconds before impact.
No mention of Mirage's arrival to the battle? Especially Rainbow Dash's Dynamic Entry, weaponizing the Sonic Rainboom...but not as a ramming attack; nope! She uses the shockwave to knock down a whole flight of Exile fliers! Capped off with a casual line:
Rainbow Dash: Sorry for the hold-up.
Fluttershy has a Freak Out at seeing the destruction the Exiles are causing, drops her lingering reservations about fighting...and delivering a powerful punch to an exile Pegasus while screaming in rage. Firefly remarks on how she will avoid making her angry at all costs.
Chapter 4 has two awesome moments as well:
First, a heroic one: Sunburst and his Phoenix squadron appear in the nick of time to prevent a bombing run on Ponyville. Also, he manages to defeat the flight leader by knocking him down, making him release the grip on the bomb he was carrying. After saying another great Pre-Mortem One-Liner, Sunburst throws the bomb at the falling enemy pegasus and finishes him off. May not be too much, but considering this Big Damn Hero entry is made by a secondary character, that really says something.
Secondly, a villianous example; Gleipnir, a huge grey dragon, reveals himself before the Mirage squadron and knocks them all out of the sky using shockwaves produced from his wings. Then, he goes to attack the ponies defending Ponyville (including Applejack and Twilight Sparkle) and... well, let's just sayhe easily turned the tide of battle.