TL; DR: Nunca é explicitado no próprio texto, mas há algumas opções para quem é provável que seja. Vou listá-los mais ou menos na ordem mais provável, embora Tywin Lannister seja o candidato mais provável.
Ned teve que fazer uma causa comum com os Lannister depois da Rebelião de Robert devido a Tywin financiar os Sete Reinos e Robert ter se casado com Cersei. Ele não parece ter superado algumas de suas ações.Tywin Lannister
Ele deixa claro nessas passagens que ele desconfia de Tywin e não se importa com ele, indo tão longe a ponto de estar preparado para insultá-lo.
Ned would sooner entrust a child to a pit viper than to Lord Tywin, but he left his doubts unspoken. Some old wounds never truly heal, and bleed again at the slightest word. "The wife has lost the husband," he said carefully. "Perhaps the mother feared to lose the son. The boy is very young."
...
"A generous offer, my friend," the king said, "but too late. Lord Tywin has already given his consent. Fostering the boy elsewhere would be a grievous affront to him."
"I have more concern for my nephew's welfare than I do for Lannister pride," Ned declared.
A Game of Thrones, Eddard I
Ele também pensa em Tywin como um assassino de inocentes e parece desprezá-lo ainda por dar ordens para matar as crianças.
Ned did not feign surprise; Robert's hatred of the Targaryens was a madness in him. He remembered the angry words they had exchanged when Tywin Lannister had presented Robert with the corpses of Rhaegar's wife and children as a token of fealty. Ned had named that murder; Robert called it war. When he had protested that the young prince and princess were no more than babes, his new-made king had replied, "I see no babes. Only dragonspawn." Not even Jon Arryn had been able to calm that storm. Eddard Stark had ridden out that very day in a cold rage, to fight the last battles of the war alone in the south. It had taken another death to reconcile them; Lyanna's death, and the grief they had shared over her passing.
This time, Ned resolved to keep his temper. "Your Grace, the girl is scarcely more than a child. You are no Tywin Lannister, to slaughter innocents." It was said that Rhaegar's little girl had cried as they dragged her from beneath her bed to face the swords. The boy had been no more than a babe in arms, yet Lord Tywin's soldiers had torn him from his mother's breast and dashed his head against a wall.
A Game of Thrones, Eddard II
Ele também pensa no homem como desonroso para quando ele traiu o rei louco durante o saque de Porto Real.
"Not our men," Ned said patiently. "Lannister men. The lion of Lannister flew over the ramparts, not the crowned stag. And they had taken the city by treachery."
The war had raged for close to a year. Lords great and small had flocked to Robert's banners; others had remained loyal to Targaryen. The mighty Lannisters of Casterly Rock, the Wardens of the West, *had remained aloof from the struggle**, ignoring calls to arms from both rebels and royalists. Aerys Targaryen must have thought that his gods had answered his prayers when Lord Tywin Lannister appeared before the gates of King's Landing with an army twelve thousand strong, professing loyalty. So the mad king had ordered his last mad act. He had opened his city to the lions at the gate.
A Game of Thrones, Eddard II
Jaime Lannister
Como Tywin, ele não parece confiar em Jaime muito na esperança de que Robert não o nomeie Warden para o Oriente porque isso significaria que ele acabaria por manter o Est e o Ocidente.
Novamente, ele reitera que não confia em Jaime e até mesmo soletra claramente para Robert. Ele até pensa que é desonroso por se sentar no alto do Trono de Ferro. Ele também parece não gostar da arrogância e arrogância de Jaime."Kingslayer," Ned said. The rumors were true, then. He rode on dangerous ground now, he knew. "An able and courageous man, no doubt," he said carefully, "but his father is Warden of the West, Robert. In time Ser Jaime will succeed to that honor. No one man should hold both East and West." He left unsaid his real concern; that the appointment would put half the armies of the realm into the hands of Lannisters.
A Game of Thrones, Eddard II
"Can you trust Jaime Lannister?"
"He is my wife's twin, a Sworn Brother of the Kingsguard, his life and fortune and honor all bound to mine."
His sword helped taint the throne you sit on, Ned thought, but he did not permit the words to pass his lips. "He swore a vow to protect his king's life with his own. Then he opened that king's throat with a sword."
"Seven hells, someone had to kill Aerys!" Robert said, reining his mount to a sudden halt beside an ancient barrow. "If Jaime hadn't done it, it would have been left for you or me."
...
"I cannot answer for the gods, Your Grace … only for what I found when I rode into the throne room that day," Ned said. "Aerys was dead on the floor, drowned in his own blood. His dragon skulls stared down from the walls. Lannister's men were everywhere. Jaime wore the white cloak of the Kingsguard over his golden armor. I can see him still. Even his sword was gilded. He was seated on the Iron Throne, high above his knights, wearing a helm fashioned in the shape of a lion's head. How he glittered!"
"This is well known," the king complained.
"I was still mounted. I rode the length of the hall in silence, between the long rows of dragon skulls. It felt as though they were watching me, somehow. I stopped in front of the throne, looking up at him. His golden sword was across his legs, its edge red with a king's blood. My men were filling the room behind me. Lannister's men drew back. I never said a word. I looked at him seated there on the throne, and I waited. At last Jaime laughed and got up. He took off his helm, and he said to me, 'Have no fear, Stark. I was only keeping it warm for our friend Robert. It's not a very comfortable seat, I'm afraid.'"
The king threw back his head and roared. His laughter startled a flight of crows from the tall brown grass. They took to the air in a wild beating of wings. "You think I should mistrust Lannister because he sat on my throne for a few moments?" He shook with laughter again. "Jaime was all of seventeen, Ned. Scarce more than a boy."
"Boy or man, he had no right to that throne."
ibid
Gregor Clegane
Pode-se argumentar que Ned nunca realmente fez uma causa comum com Gregor, mas ele montou ao lado dele e foi forçado a aturá-lo devido a sua lealdade comum com os Lannister. Ned parecia não gostar, desconfiar de Gregor e até acreditar nos rumores sobre o cavaleiro e que ele era o único a matar Elia e os bebês.Unlike his brother, Ser Gregor did not live at court. He was a solitary man who seldom left his own lands, but for wars and tourneys. He had been with Lord Tywin when King's Landing fell, a new-made knight of seventeen years, even then distinguished by his size and his implacable ferocity. Some said it had been Gregor who'd dashed the skull of the infant prince Aegon Targaryen against a wall, and whispered that afterward he had raped the mother, the Dornish princess Elia, before putting her to the sword. These things were not said in Gregor's hearing.
Ned Stark could not recall ever speaking to the man, though Gregor had ridden with them during Balon Greyjoy's rebellion, one knight among thousands. He watched him with disquiet. Ned seldom put much stock in gossip, but the things said of Ser Gregor were more than ominous. He was soon to be married for the third time, and one heard dark whisperings about the deaths of his first two wives. It was said that his keep was a grim place where servants disappeared unaccountably and even the dogs were afraid to enter the hall. And there had been a sister who had died young under queer circumstances, and the fire that had disfigured his brother, and the hunting accident that had killed their father. Gregor had inherited the keep, the gold, and the family estates. His younger brother Sandor had left the same day to take service with the Lannisters as a sworn sword, and it was said that he had never returned, not even to visit.
A Game of Thrones, Eddard VII
Roose Bolton
Estou mencionando o Roose aqui porque ele é mencionado na pergunta e há uma pequena chance dele, mas eu duvido muito. Na verdade, tenho certeza de que não é para ele.
Os Stark's e os Bolton estão em conflito um com o outro há tanto tempo quanto o de Stark e Bolton. Então você diria que este seria um candidato provável e os dois tiveram que se beijar e compensar a Rebelião de Robert, a Rebelião Greyjoy e na maioria das corridas do Norte.No entanto, a única menção de Roose, ou qualquer Bolton para esse assunto, nos capítulos de Eddard é o seguinte. Não é um pensamento positivo de Ned.
"Mercy is never a mistake, Lord Renly," Ned replied. "On the Trident, Ser Barristan here cut down a dozen good men, Robert's friends and mine. When they brought him to us, grievously wounded and near death, Roose Bolton urged us to cut his throat, but your brother said, 'I will not kill a man for loyalty, nor for fighting well,' and sent his own maester to tend Ser Barristan's wounds." He gave the king a long cool look. "Would that man were here today."
A Game of Thrones, Eddard VIII
Rhaegar Targaryen é mencionado na pergunta, então eu vou falar com ele aqui, mas não acho que Ned o tenha desprezado. De fato, a maioria de suas lembranças de Rhaegar na verdade parecem ser bastante positivas, por exemplo ...
Na verdade, ao ver Rhaegar dar Lyanna a rainha do louro de beleza em vez de sua própria esposa e sabendo sobre seu relacionamento. Mesmo indo tão longe quanto aThere was no answer Ned Stark could give to that but a frown. For the first time in years, he found himself remembering Rhaegar Targaryen. He wondered if Rhaegar had frequented brothels; somehow he thought not.
A Game of Thrones, Eddard IX
look after Jon and hide him away.
É provável que Ned tivesse algum respeito pelo homem e provavelmente não o desprezasse apenas por respeito a Lyanna.
Robert had been jesting with Jon and old Lord Hunter as the prince circled the field after unhorsing Ser Barristan in the final tilt to claim the champion's crown. Ned remembered the moment when all the smiles died, when Prince Rhaegar Targaryen urged his horse past his own wife, the Dornish princess Elia Martell, to lay the queen of beauty's laurel in Lyanna's lap. He could see it still: a crown of winter roses, blue as frost.
A Game of Thrones, Eddard XV