Catelyn Stark successfully holding off an assassin that is attempting to kill her recently crippled son that is lying in a coma, with her even stopping a Valyrian Steel dagger with her bare hand.
Another for Catelyn: when she is outed by an oblivious Tyrion at Masha Heddles inn, she quickly reminds every swordman present that she is the daughter of their liege lord and needs their help. They quickly surround Tyrion and his party.
Jon successfully intimidates Rast, the violent rapist new recruit, into stop bullying Sam. With the help of Grenn and Pup they immobilize him and lets Ghost nip at Rast's throat with his fangs, quietly telling him:
Jon: Remember, we know where you sleep.
Nymeria saving Arya by attacking Joffrey, and Arya taking Joffrey's sword and throwing it in the river.
When the Hound stops Loras Tyrell from being killed by Gregor Clegane. The Mountain, Westeros's One-Man Army is almost definitely the strongest man on the planet, stronger than even Hotah, Victarion, Andrik, Robert, Goghor, and Hodor, among others. Despite this, the Hound hops out of the stands and stops him. This is the only time one ever sees a warrior that is not a Fragile Speedster directly go head-to-head with Gregor and not lose awfully. After killing Mycah, this is the point when readers truly begin to sympathise with Sandor and the backstory he had.
It is even implied that Sandor could have won that fight, and more importantly, could have killed Gregor if he wanted to. Ned points out to himself that while Gregor swings for Sandor's head multiple times, Sandor never tries this despite Gregor having removed his helmet. Sandor didn't just not die (which would be a victory for most) but he also completely humiliated his brother in front of most of King's Landing, and proved himself the deadlier fighter to anyone with the experience to notice.
Tyrion manages to escape certain execution by demanding a trial by combat and turns Bronn, a dangerous and highly skilled mercenary, to his cause. And when Lysa Arryn makes him go down a mountain pass inhabited by Proud Warrior Race Guys who have been the scourge of the Vale of Arryn for centuries, he manages to convince them to let him safely go through the pass and serve him as bodyguards and enforcers. And he actually upholds the promises he made to them instead of saying "Suckers!" once he's safely in his own army.
It gets better. The Promise he made was to ARM the Mountain Clans with steel armor and swords who then go back and use them to raid the Vale of Arryn. So he gets through the pass, gets body guards and enforcers, and his payment gets revenge on the woman who imprisoned him, all at the same time!
Unfortunately the clansmen use their new steel weapons not to attack Arryn forces but to raid & pillage hapless peasant villages, many of which are not even in the Vale but rather in the Riverland fringes. So in the end the smallfolk end up paying for Tyrion's scheme.
When the mountain clans get the drop on Tyrion and Bronn, they're outnumbered a dozen to two. Shagga tells his men to kill Bronn and bring Tyrion. Bronn's response of to draw his blade and ask who wants to die first.
A great one for Littlefinger is when he betrays Eddard Stark, saying "I did warn you not to trust me, you know."
Adds another layer of awesome when you look back at Cat's character and relationship with Littlefinger before her husband's death and realize that he would've had a chance at getting back with her if not for a Spanner in the Works by the way of Joffrey (Eddard was supposed to be sent to the wall, which involves giving up his wife.)
When foreign weapon-master Syrio Forel is confronted by five Lannister fully armoured men-at-arms and one of the knights of the Kingsguard, while he himself is armed with a wooden practice sword. The quote above was swiftly followed by the death of the men-at-arms. He only lost the fight because the knight had no gaps in his armor which Forel could use to kill him.
Never trust that a character is truly dead unless it is witnessed and confirmed by another POV character.
And even then...
"What do we say to the god of death?" "Not today."
While his morality is deplorable, one has to respect Gregor Clegane's might. He, and a dozen other knights, charges headlong towards an entire formation of Karstark spearmen. Despite almost all of the other knights being driven off or killed, Clegane powers straight through the spears and crash directly into the Karstark heavy infantry, probably killing four or five at least. Then, he rises, completely unscathed, and then begins to wield his BFS with a single hand, smashing every enemy in the vicinity into oblivion with contemptuous ease. Seconds later, the Mountain Clans pile in. Were it not for Clegane's sheer power, the mounted Clansmen might have been driven off by the spearmen, and the entire left flank might indeed have been driven off, as Tywin had originally planned.
Tywin's plan for that battle. Either the flank holds, in which case, good job, the battle is won, celebrations for everyone. Or the flank fails to hold, in which case there is high possibility that his dwarf son he hates so much will be killed, with no danger to Tywin because his reserves and main force are ready to jump in classic pincer maneuver and push the enemy into the river and slaughter them.
Robb's continuing victories over the Lannisters, culminating in the climactic "King in the North!" moment at the end of the book.
Everything Eddard Stark did in a single book. His first action is to behead a deserter himself, proving that hands-on justice is the best kind. He has the honor to accept his bastard child Jon Snow, and his What the Hell King speech to King Robert when he orders that Dany and her brother killed to protect the Seven Kingdoms is a bastion of morality. And then he voluntarily gives up what could be considered the strongest political position in the entire world just to prove that he wouldn't go along with it.
With a little thinking it gets even better. He has virtually no experience with the Game of Thrones and yet he hurls himself in with no apologies whatsoever and is making headway to fix the kingdom. His actions motivate Cersei, Varys, and Baelish to accelerate their plans because they are afraid of him as Varys's discussion with Illyrio proves. In the end it takes a combination of Littlefinger betraying him, being high on milk of the poppy, wounded by Jaime Lannister, Robert dying, and (admittedly not too brightly) telling his intentions to Cersei. This is the kind of luck that could kill Xanatos himself and it took all that to bring him down. Not bad for the second son from a relatively isolated province.
Throughout the book, Sansa Stark has been raised to believe in fairy tales and Prince Charming and expecting her life to be storybook-perfect. Then she finds herself in the midst of a coup; then she sees many of her family's servants and guardsmen slaughtered; then she sees her beloved husband-to-be order her father's head chopped off; then she sees his head get chopped off; then her betrothed, who has recently come into his own as the Almost Trope Namer for "Royal Brat," orders his Praetorian Guard to beat her until she complies; then she's paraded to the top of the wall to look at the head. And the Trauma Conga Line has the most amazing result: the inner steel she's always had comes out to view. And everyone who dismissed Sansa as a Smitten Teenage Girl who would get chewed up and spit out by the game of thrones — which, to be clear, is the majority of readers who have made it this far — suddenly discovered just how wrong we were. The Guile Heroine of the franchise has been born.
A kind of madness took over her then, and she heard herself say, "Maybe my brother will give me your head."
A small moment, but when she cleverly mamages to avoid a fight between Joffrey and Renly by deducing who he and Barristan Selmy are, charming the group and even making everyone laugh with a joke about Ilyn Payne (who she'd just had a near panic attack meeting).
Sansa, the friendless "traitor's daughter", Sansa who nobody sees as a threat or particularly clever or strong, goes up to beg for Ned's life in front of the whole court.
Sansa quailed. Now, she told herself, I must do it now. Gods give me courage. She took one step, then another. Lords and knights stepped aside silently to let her pass, and she felt the weight of their eyes on her. I must be as strong as my lady mother.
Anytime that Dany humiliates Viserys, first by shoving him away and forcing him to walk behind the Dothraki khalasar for an entire day, then hitting him with a gold-plated belt. Considering that when we first see her she's merely a scared thirteen-year-old girl, this is some major character development.
Pretty much everything we see of Dany after her wedding sees her grow increasingly strong. The book ends with her hatching three dragon eggs on a funeral pyre, and succeeding, finishing by walking into the flames and carrying the dragons out again, almost entirely unscathed. And then she gets Jhogo, Aggo, and Rakharo to become her bloodriders, despite the Dothraki never allowing a woman to do this before. She came a long way, and this is only the beginning of her epic journey to reclaim her family's throne.
As Daenerys Targaryen rose to her feet, her black hissed, pale smoke venting from its mouth and nostrils. The other two pulled away from her breasts and added their voices to the call, translucent wings unfolding and stirring the air, and for the first time in hundreds of years, the night came alive with the music of dragons.
Jorah defending Dany from Drogo's bloodrider. Epicness ensues.
Jorah: Horselord! Try me!
Jaime gets one off screen at the Whispering Woods. His army is being tactically outmanoeuvred and overpowered by Robb Stark's ambush and he knows it. His response, the only thing that might still turn the tide of battle- he leads a charge at Stark himself hoping to kill him, cutting through dozens of men and would have succeeded and turned a resounding defeat into a victory with his personal prowess alone if he hadn't gotten his sword stuck in the corpse of one of Robb's bodyguards.
Jon showing off that he's more than just a good fighter by giving a speech to Maester Aemon to convince him to take on Sam as his assistant, sparing him from Alliser Thorne's potentially lethal Training from Hell. Most of all this line, which shows a better understanding of the value of non-fighters than most of Westeros's Proud Warrior Race Guy culture:
Jon: You can't hammer tin into iron, no matter how hard you beat it, but that doesn't mean it's useless.
Arya rightfully pointing out that her late friend Mycah is completely innocent and Joffrey had him killed out of spite, and Sansa has the gall to claim that he deserved it for attacking her prince. Arya calls her a liar (Sansa did witness the whole event but denied what really happened, which led to her own direwolf’s death) but her older sister spitefully tells her to call her whatever she wants for now, until she marries Joffrey. Then Arya will be forced to bow before Sansa and call her Your Grace. Arya’s response? Throw an orange at Sansa’s face and ruin her perfectly white dress. Lesson in point, don’t mock Arya’s dead friends.
