"A good man does everything in his power to better the position of his family," Tywin said just a few days before Tyrion killed him with a crossbow. But Tywin, son of Tytos of house Lannister, was no good man. He was a dangerous person to be around as he would stop at nothing to eliminate the threats to the dominance of his house in Westeros.

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Of all the Lannisters in Game of Thrones, Tywin and Cersei were the most evil by far. Cersei massacred the Tyrells and the faith militant with them when they threatened to take away her throne. Tywin, on the other hand, paid off Walder Frey to wipe out the Starks at the Red Wedding, which was too evil even for war. So, who was the worst Lannister between these two powerful people that ruled King's Landing for years, and what made them so terrible?

Tywin: His Treatment Of Tyrion

Tywin Lannister lectures Tyrion in Game of Thrones

When Tyrion asked Tywin to mention any time he had done something for House Lannister and not for himself, he said that when Tyrion was born, he wanted to drown him in the sea, but he let him live and carry his name. Tywin hated Tyrion with passion.

Tywin was even disappointed when Tyrion managed to come back from the Eyrie alive. He never congratulated Tyrion for his smart play at the battle of Blackwater Bay; in fact, he took advantage of Tyrion's Mud-Gate attack and gave him no credit for it.

Cersei: She Refused To Send An Army To Winterfell

Cersei Refusing To Join In The Great Battle of Winterfell

The Battle of Winterfell was a threat to everyone alive. If the Night King won the battle, he would have marched south to finish off King's Landing. Cersei was right about whoever won the Battle of Winterfell coming south to attack King's Landing, but she would have changed her own fate and that of King's Landing by sending an army North as she had promised.

Surely, even the evilest person on Earth needs to be alive to continue being evil, but not Cersei Lannister. She chose to turn it into an opportunity to strengthen her army for an invasion against people who were fighting for everyone alive. Her cunning was too much even for Tyrion this time around, since she had more reason to live than fight but still refused to take it.

Tywin: His Slave Camp In Harrenhal

Maisie Williams and Charles Dance in Harrenhall

When Tywin was at war with the Starks during the War of The Five Kings, he used Harrenhal as his forwarding base, but it was more of a torture camp. When Arya, Gendry, and Hot Pie were captured by the Lannisters and taken to Harrenhal, they found The Mountain and The Tickler torturing small boys while looking for information on the whereabouts of the Brotherhood Without Banners.

When Tywin came to observe the horror the castle had turned into, he didn't seem much bothered by Gregor Clegane's inhumanity. All he asked was for Clegane to spare the remaining smallfolk and turn them into slaves to serve his army instead.

Cersei: The Massacre Of The Great Sept Of Baelor

The Destruction Of The Great Sept of Baelor

Who sets up a bomb to blow up a court just before their own trial? Margaery Tyrell knew she had underestimated Cersei when she realized that House Tyrell and all of Cersei's enemies were the only people at the trial, but it was too late. Cersei did something similar to what her father did to the Starks at The Red Wedding.

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She didn't care about the faith, the gods, and her son's feelings, all she saw was The High Sparrow and the Tyrells gathered under one roof that she take out in one fell swoop. Blowing up the Sept of Baelor changed Game of Thrones drastically, as it ended the Tyrells, led to Tommen's death, and of course, made Cersei the most powerful woman in The Seven Kingdoms.

Tywin: He Massacred House Reyne

Charles Dance as Tywin Lannister in GOT s03

The Rains of Castamere is the song that has immortalized Tywin's massacre of House Reyne and House Tarbeck. The two houses rose in rebellion against Tytos, Tywin's father, who was a weak leader.

Young Tywin marched the Lannister army on the two houses and killed all of them, hanging their corpses on the walls of Casterly Rock to rot all summer in the view of everyone in the Westerlands. It was the beginning of the dominance by fear of House Lannister.

Cersei: Her Revenge On The Martells

The Poisone Kiss on Tyene Sand

Ellaria Sand was wrong to use the Poisoned Kiss on little Myrcella who had nothing to do with Oberyn Martell's death, but Cersei's revenge was too extreme. Tyene Sand was not as innocent as Myrcella, but she had done nothing that wasn't directed by her mother. Cersei should have taken revenge on Ellaria directly.

The worst bit was that Ellaria would have to sit and watch her daughter die and rot away right there in front of her in the cell. It was probably the cruelest act a mother could do to a fellow mother, and that's exactly why Cersei did it.

Tywin: He Sentenced Tyrion To Death

Tywin knew that Tyrion had nothing to do with Joffrey's death but still condemned him to death just to fulfill his long-term wish of doing away with him. He just stood by to watch the whole trial with Tyrion begging and getting tortured by all the fake witnesses without doing anything.

When the battle by combat was lost, Tyrion's fate was at the hands of a father who hadn't cared about him since he was born. If Jaime and Varys didn't come together to save Tyrion, Tywin wouldn't have hesitated to carry out Tyrion's execution.

Cersei: She Was Unmoved By Tommen's Death

Tommen Baratheon's death

Cersei was either the worst mother in history, or she just didn't care about Tommen. During the Battle of Blackwater Bay, she wanted to poison herself and Tommen when she thought the crown would be lost to Stannis Baratheon. Tommen's eventual death was also her fault, as she undermined everything he did and killed the woman he had grown to love.

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When she was told of her only surviving child's death, she didn't seem to care at all. It is unclear how her heart darkened so much, but for some reason, she just didn't have that heart of a mother anymore. Ignoring her son's death and ordering him to be buried in the rubble with her enemies was the peak of her evil.

Tywin: The Red Wedding

Robb, Talissa and Catelyn Stark at the Red Wedding

When Tywin bragged to Tyrion about how he had massacred a dozen Starks at a wedding to prevent further deaths, Tyrion told him the North would remember. He retorted, saying they will know what happens when they march their armies against the south. Killing Robb and Catelyn Stark at the Red Wedding was evil and even broke guest right, a most sacred rule of Westeros.

Even though the act ended the War of The Five Kings, it created an irreparable rift between the Starks and the Lannisters, and therefore the kingdoms themselves.

Cersei: Killing Missandei

Missandei on Dragonstone in armor in Game of Thrones

Missandei was an innocent translator with no combat ability. She had a good heart and was probably the only person left that could or would have convinced Daenerys against burning down King's Landing.

She didn't listen to Tyrion's reason and seemed very pleased at the horrified faces of Daenerys and Grey Worm when she executed her. It would take someone with a very cold heart to kill someone like Missandei just to send a message. Killing Missandei effectively made Cersei the worst Lannister in the show.

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