Eddard Stark
He was leading the rebel armies to take the King's Landing after the battle of the Trident, there wasn't a lot of hurry since everyone knew that the main opponent was already defeated, but then they heard from the scouts about Lannister army marching towards the capital. They had to increase the speed of the march, since they weren't sure about the intention of Tywin Lanniser who earlier ignored any message requesting support of their armies, if they were to help in defence of Red Keep the siege may prove to be way harder and longer then expected, if they didn't hurry now Tyrells might come back from the south and aid the lions in defence, and he wasn't sure they would win next major battle with such ease.
If he had to guess, he would expect that Lannisters already heard about the result of the battle, and they would join them soon, that's why he was so surprised that they had already marched on King's Landing.
When thy finally caught up to the army of wester landers, and saw the gates opened for them he finally understood what Tywin Lannister wanted to achieve. His plan was simple take King's Landing and gift it to Robert endearing himself to the future king. He had a bad feeling about this since almost everyone in the seven kingdoms heard of The Rains of Castamere. That's why instead of going straight for the king he took a few of his loyal bannerman and went for Maegor's Holdfast instead to make sure the royal family will not be harmed while Jon Arryn went to the Great Hall.
What he found inside the royal apartments made his blood boil, seeing the knight Amory Loch drag a young girl from under the bed intent on stabbing her made him react and he quickly engaged him in combat and quickly stabbing him through the heart just like he wanted to do to the royal child a mere moments ago. He quickly took Rhaenys Taergaryen with him assuring her that she will be safe with him just before other lords told him that they found blood in the next room.
Next thing he knew he was standing before Robert who sat on the throne smiling while Tywin Lannister presented him with the bodies of Elia Martell and Aegon who was a faceless horror of bone and brain and gore and everyone believed Tywin when he said who it was.
"Now" said Robert "What ought we to do with you." looking at the young girl who tried to hide behind Ned' own legs.
"We should kill you now and be rid with you dragonspawn once and for all" he continued.
"My King" said shocked Ned not expecting this out of his best friend "perhaps we should send her to Dorne to begin repairing the relationship with the Martells, we both know they don't love the Targaryens as they once did after Rhaegar dishonered his dornish bride."
"No" objected Robert "we can't do that we will not give any chance for usurpers to rise."
"Then let me raise her in Winterfell, I shall make sure she is loyal to the crown" pleaded Ned, "let's not shed any more of innocent blood this day."
"No dragonspawn is innocent of sin she will grow up to be mad like her fathers before her" said Robert "but if that is what you want, you will raise her in the North, but if I hear that she even thinks that she has any claim to the throne you will cut her head yourself."
"If that is your will" agreed Ned.
And with that decision some of the courtiers who survived the sack already began to praise King Robert for how merciful and thoughtful he is, the same courtiers which few hours earlier were ready to praise the burning of Eddard's father and killing his brother. He wanted to go back North already.
Before Robert could crown himself King of the Andals, the Rhoynar, and the First Men, Ned was already on the battlefield again lifting the siege of the Storm's End which was surprisingly easy since Mace Tyrell and Paxter Redwyne surrendered at the first sight of the rebel army, such was might of the Reach.
It disgusted him that while he was lifting the siege of his brothers, Robert was crowning himself and celebrating the death of Targaryen child. He couldn't see his best friend doing that a year ago, but now it was happening.
He left Rhaenys safe in the Storm's End with Stannis whom he knew as an honourable lord who wouldn't be happy to hear about killing of children. And after that he travelled with a few companions to the Tower of Joy.
Seeing the Red Mountains of Dorne he felt anything than joy, he knew that soon he would have to face the brother of the woman he was supposed to marry before that folly of Rhaegar. He rode with his companions Proud Martyn Cassel, Jory's father; faithful Theo Wull; Ethan Glover, who had been Brandon's squire; Ser Mark Ryswell, soft of speech and gentle of heart; the crannogman, Howland Reed; Lord Dustin on his great red stallion.
Seven of them would face three, but three of the best Westeros had to offer, among them Ser Arthur Dayne, the Sword of the Morning, stood with a sad smile on his face.
"I looked for you on the Trident," Ned said to them.
"We were not there," Ser Gerold answered, "Woe to the Usurper if we had been."
Indeed, he thought, such warriors could do a difference on the battlefield, who knows what could have happened if they were there.
"When King's Landing fell, Ser Jaime stabbed your king with a golden sword, and I wondered where you were." Ned responded.
"Far away," Ser Gerold said.
"I thought you may have fled like Ser Willem Darry."
"Ser Willem is a good man and true" said Ser Oswell "But not a Kingsguard. The Kingsguard does not flee."
"We swore a vow" explained old Ser Gerold.
They were seven against three. And yet it would haunt him for the rest of his life when Ser Arthur Dayne unsheathing the Dawn said the words.
"And now it begins."
He lived this skirmish, but only thanks to the crannogman Howland Reed. Now he had to find Lyanna, and he found her in closed in small room looking worse than ever.
"Ned… I'm sorry" she said with her voice weak from the fever.
"Lyanna it's not your fault, you will be alright" he assured her.
"The maester he brought said I don't have a lot of time" Lyanna said "Ned promise me you will do what's best for the North, as I should. Promise me"
"I promise" he whispered.
Soon after that she drew her last breath, and he sent Lord Reed with the body, while he travelled with Dawn to Starfall.
After returning the Dawn he saw Ashara looking at him with her sad purple eyes. He wanted to talk to her, but he couldn't bring himself to do it. What could he say to the woman he promised to marry, and instead he brings her family the news that he killed her brother.
"You can only be brave when you are scared" those words ringing in his ears.
And yet it would stay on of his many regrets of the rebellion, knowing that he can never say the words he wanted after hearing of her death.
There was one thing he didn't regret he thought while riding for Winterfell and that was saving Rhaenys Targaryen.