Robb Starks' dissatisfied bannermen — Walder Frey and Roose Bolton — to finish the Stark forces and claim at "The Red Wedding" massacre. Roose executes Robb while taunting "the Lannisters send their regards", Robb's mother Catelyn and wife Talisa are brutally killed as well. When news of Robb's death reaches the Lannisters, Tyrion quickly deduces that his father masterminded the event. Tywin confirms this and shrewdly observes that this means the Freys will get all the credit but also all the blame — since the Northerners will never forget nor forgive such a terrible crime. Tywin senses that his son finds the action dishonorable but insists it was done to protect the family and end the war. He is forced to contend with an increasingly belligerent Joffrey, who insists that his father Robert (refusing to believe the claim regarding his parentage) won the war by his sword, while chiding his grandfather as a coward who "hid under Casterly Rock". Tywin sends his grandson to bed and promises to teach him the realities of ruling, before reminding Tyrion of Joffrey's limited power and of his husbandly duty to impregnate Sansa and again insists that a man who puts family first will always triumph. When Tyrion asks his father whether he has ever put the family's interests ahead of his own, Tywin retorts by stating his desire to euthanise Tyrion at birth out of rage and grief but instead let Tyrion live and ended up raising him "as my son", showing that he has disowned his parentage of Tyrion as well. Season 4 Tywin has the Stark ancestral sword Ice melted down into two swords, one of which he gives to Jaime, though he disowns him after Jaime refuses to resign from the Kingsguard to become Tywin's heir. When Tyrion is accused of poisoning Joffrey, Tywin asks Oberyn Martell to serve as one of the judges in Tyrion's trial. Though Oberyn despises Tywin for ordering the death of his sister, niece and nephew during the sack of King's Landing, he agrees when Tywin offers him justice against their murderer, Gregor Clegane. Tywin also presses Cersei to wed Loras Tyrell to use House Tyrell's wealth to pay off the Crown's debts to the Iron Bank of Braavos but is forced to back down when Cersei threatens to reveal her incestuous affair with Jaime. Tywin has an affair with Shae, Tyrion's former mistress. Tyrion