The answer to the Call: the Wall finds itself swamped by volunteers, the Company of the Rose crosses the Narrow Sea back to help their long-lost cousins, and of course, all those lords and ladies pledging themselves to Ned, the Stark in Winterfell with two words: "Command us!".
In Chapter 37, Theon stands up to his brother's ghost and outright rejects the Drowned God.
Rodrik: You are a... Greyjoy, boy! You serve... the Drowned God.
Theon: No. I do not.
Chapter 45, in which Jon Arryn reveals his champion in Baelish's trial by fight: the sea.
Earlier, when Jon mentions to Baelish that he's told a representative of the Iron Bank who "happened to be passing by" about how Baelish had lied to the Iron Bank and stole money from the loans they gave the Seven Kingdoms, Baelish panics, telling Jon that the Iron Bank doesn't just "happen" to have representatives in the area, and that the man is most likely a FacelessMan sent to kill Baelish. Jon's response?
All of Gendry's actions when the ship that's taking him to Storm's End gets hit with a storm - from cutting the damaged mast free before it can capsize the ship, to using the chain pump for hours on end to keep the ship from sinking. It all earns him a new epithet among the crew - Gendry Strongarm.
A low-key yet admirable one when Samwell Tarly manages to find Otherbane, the legendary weapon wielded by the Gardener kings, with his smarts. He's not gloating when he and his father present the weapon to Willas Tyrell, but you know he will hold this over daddy dearest's head for a loooooong time.
The revelation of just who the Green Man is: The long thought dead Ser Duncan the Tall, former Lord Commander of the Kingsguard.
After protecting the God's Eye from a fanatical mob, Robar is rewarded by being knighted by no less a Living Legend as Ser Duncan the Tall.
Edd Tollett becomes the first Black Brother in many millenia to dispatch an Other while protecting Craster's latest son from the creature.
Both the First and the Second Battle of Harlaw. Using the intelligence men like Balon Greyjoy deride, Rodrik Harlaw is more than capable at turning his enemies' strategies against them, successfully defending his island from those Ironborn who have not accepted the Call and even knocking out Victarion Greyjoy in single combat.
The Battle of the Nightfort. More like a scuffle, really, but Robb truly shines, particularly thanks to Ice, which allows him to utterly destroy every man that fights him. Ser Alliser gets to kill more than three, as do Jon and Theon.
Stannis intimidating the shit out of Joffrey when the brat tries to bully Shireen and Gendry. The prince wouldn't want for Stannis to get annoyed, right?
The Battle of the Black Gate. Coldhands arrives, injured and pursued by wights, and the Nightfort expedition - now with the addition of Benjen Stark - fights the wights off, with Tyrion using Rocktooth for the first time and destroying several wights. Then, four Others come, and Gerion jumps forward, proving Valyrian steel as a weakness. Jon and Robb follow, each fighting and killing an Other, while the fourth attacks the rest of the group - and Tyrion stops him cold by parrying with Rocktooth and then turning the Other into tiny pieces with the axe.
Of particular note is Gerion - when faced against the Others, he has two great lines when he realizes that they have never encountered Valyrian Steel before.
The ride from Castle Black to Winterfell. It takes the group only THREE DAYS to reach Long Lakenote A reader noted that the distance between Castle Black and Long Lake was about 480 km.! When Greatjon mentioned that Ned could make himself and others move at a fast pace, he was not kidding.
With the reveal about Dawn rejecting Arthur Dayne for his actions, the fight at the Tower of Joy becomes even more impressive for Arthur Dayne, who essentially fought off an enemy that heavily surpassed him in number and nearly won, with a sword that was actively fighting him off.
During the trial of Willem Bootle, Eddard dares him to swear an oath on the Fist of Winter that he did not kill Lord Surestone. Bootle, after declaring he was not afraid of legends and heathen symbols, does so. A few seconds later, Bootle dies - essentially fried by the Fist. To round it, Eddard drops a Bond One-Liner:
Eddard Stark: Perhaps you should have been afraid, then.
It took 154 chapters (54 for the Fanfiction.net version) since Ned Stark first mentioned repairing the Broken Tower, but readers finally got to see Cersei and Jaime getting caught in the middle of sex and arrested.
When Jaime and Cersei get caught, the first to act is Ser Barristan, who despite his age grabs Jaime by the back of the neck, throws him against a wall so hard to leave Jaime rattled, and starts throttling the life out of him, while snarling that he will burn Jaime's white cloak using his page in the White Book as kindling and declaring him without honor and no knight.
Robert is now mature enough to realize that going to meet Cersei and Jaime after learning of their incestuous relationship will not be a good idea, and accepting that he needs to calm down and think rationally. A good depiction of all his Character Development thus far.
Adding to that, using Stormbreaker to identify the parentage of his children in a way that doesn't embarrass anyone... much.
Later, when confronted by Cersei's threats and taunts, Robert is driven to the point of pure unadulterated rage and nearly attacks her... only for him to stop himself before anyone else tries to halt him, having seen through her Wounded Gazelle Gambit. Considering how much of an impulsive man he usually is, and that he is faced with one of the people he hates the most in the world, that took a LOT of self-control.
Then, Gerion telling Jaime off and saying he's not worthy of wielding Brightroar.
Robert wields Stormbreakerone-handed, with a shield. Remember that this is a greatsword about the same size as Ice, which is said to be almost as tall as Robb.
Remember how, during Robert's training session in the Red Keep in chapter 58, Jaime's sword rusted from the inside and shattered? Well, Robert does, and as the combat goes, Jaime loses five swords, his helmet, his shield, and his armor, because they all rapidly rust due to Stormbreaker's penchant for Rule of Symbolism.
In the end, Jaime is left humiliated, on the ground, with no weapons or protection and with his confidence completely shot to hell. Robert tells him he's going to go to the Wall and leaves, pointing out he's not going to kill a defenseless man.
Willas, who just a few weeks earlier could barely walk without a cane, faces the entity behind the Hightower Gate and prevents it from crossing to the normal world.
Also an awesome moment for Mace Tyrell, who willingly runs closer to the Gate to get the fallen Septon and his acolyte away from it.
Is it satisfying to see Robb defend himself against a drunken and recently disinherited Joffrey, getting into a Knife Fight with him, breaking his nose and finally Val kicking him in the balls? Most definitely.
For all of his doddering, his Obfuscating Stupidity and his almost slavish devotion to Tywin Lannister, it is impressive to see Pycelle being willing to lead a group to find the wildfire caches hidden beneath the Great Sept.
Before that, Lyanna's spirit reveals she was not a complacent captive for Rhaegar; she fought off his attempts to rape her to the point that he had to have the Kingsguard hold her down, rejoiced when he died and threw it into to the faces of said Kingsguard, and, as her final act of spite, gave him a son instead of the daughter he wanted.
Ladies and Gentlemen, the Seven Hells have officially frozen over: Tywin Lannister finally admits that Tyrion has done a great job and has acknowledged him as his heir.
Tywin's EPICYou Have Failed Me speech to Cersei in chapter 135 which boils down to a 2500+ word "scaring her straight" monologue, during which Cersei doesn't even get a chance to speak.
Tywin states that Joffrey's first reaction at seeing him was to demand Tywin raise his armies, overthrow Robert, burn the North to the ground and kill everyone in it, and bring Joffrey to King's Landing and his rightful place on the throne - at which point, Tywin backhanded Joffrey across the face. He then gave him a chewing-out so severe that Joffrey is subdued as he practically begs Robert to be sent to the Wall.