"Before long I'll be dead, and you and your brother and your sister and all of her children, all of us dead, all of us rotting underground. It's the family name that lives on. That's all that lives on. Not your personal glory, not your honor... but family."
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Tywin Lannister is the head of House Lannister, Lord of Casterly Rock, Warden of the West, Lord Paramount of the Westerlands and, currently, the Hand of the King to his grandson, King Joffrey Baratheon. Intelligent, calculating, and ruthless, he is also the richest man in the Seven Kingdoms. His primary concern is his family's legacy.

vs.

"Your meat... is bloody tough!"
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The Greatjon is the Lord of Last Hearth and a formidable and proud bannerman of House Stark. He is a large, formidable warrior. He is fighting for Robb Stark in the War of the Five Kings. He is not present in the second season and it is assumed he is leading northern forces fighting elsewhere. His role as Robb's chief northern advisor is taken up by Lord Roose Bolton.