The release of House of the Dragon earlier this year in August sparked a renewed interest in the Game of Thrones universe as viewers want to learn more about the medieval fantasy world of Westeros. In all eight seasons of its long tenure, Games of Thrones provided viewers with a multitude of characters, from the morally-gray and ambiguous to the downright evil.

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HBO's Game of Thrones has its fair share of anti-hero characters and antagonists, but some of them are downright ruthless and would stop at nothing to achieve their own individual agendas, no matter the casualties. Here are some of the most ruthless characters in Game of Thrones.

9 Arya Stark

Game of Thrones, Arya killing Walder Frey

Although small, Arya Stark is dangerous, badass, and one of the more ruthless characters in Game of Thrones. She begins as a waif of a tomboy, not entirely conforming to society's expectations of girls her age, getting her first sword, nicknamed Needle, from her half-brother Jon Snow. She ends up on the run after the execution of her father, Ned Stark.

What average girl has a Kill List? Arya recited her Kill List every night as a somewhat disturbing comfort ritual. Funnily enough, every name on her list ends up dying one way or another! After endless traumatic experiences, Arya eventually becomes a Faceless assassin, using what she learned at the House of Black and White to brutally murder Walder Frey for his role in the Red Wedding.

8 Jaime Lannister

Jaime Lannister pushing Bran

Named The Kingslayer, Jaime Lannister began the show as a clear villain. He pushed a defenseless child, Bran Stark, outside a tower window after Bran accidentally discovered his incestuous relationship with his twin sister Cersei, paralyzing Bran permanently.

It's clear that Jaime was not an ally to House Stark, as Jaime was also responsible for Ned Stark's arrest at King's Landing, which later led to his execution. He also waged war against Robb Stark following Ned's death. Although Jaime emerges as an unlikely hero in later seasons, his relationship with Cersei negatively influenced most of his decisions and caused him to commit some terrible crimes.

7 Petyr "Littlefinger" Baelish

Game of Thrones, Petry Littlefinger Baelish

Without a doubt, Petry Baelish, nicknamed Littlefinger by most characters, is one of Westeros' most sinister and scheming characters. Coming from an unknown house, he was self-serving and would stop at nothing to achieve greatness and fame.

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His duplicitous behavior and silver-tongued charisma set many devious plans into motion, including the beheading of Ned Stark and the assassination of Joffrey Baratheon. He even betrayed Sansa Stark and organized her wedding to the cruel Ramsay Bolton. Many Game of Thrones fans would say that Littlefinger got his comeuppance with some divine justice at the hands of the Stark household.

6 Daenerys Targaryen

Daenerys Targaryen addresses her armies in Game of Thrones.

Daenerys Targaryen is an interesting and potentially the most controversial character on this list. Through her tenure of Game of Thrones, she was painted as a messiah and liberator for the slave cities and quite literally named the Breaker of Chains. Despite her heroic stature, she was not against burning innocent people alive to make a point.

Pushed to the brink of insanity after the deaths of her friends and her dragon children in Season 8, Daenerys finally accomplished what she'd always dreamed of. She ransacked King's Landing using Drogon, burning and slaughtering countless innocents and ironically becoming queen of the ashes. Her genetic Targaryen madness caused her tragic downfall, and her victory was short-lived as Jon Snow ended her tyranny.

5 Gregor "The Mountain" Clegane

Game of Thrones, The Mountain and Oberyn Martell

Gregor Clegane certainly lives up to his reputation and nickname of The Mountain with his gargantuan stature and brutish strength. Though viewers mainly hear secondhand accounts of his offenses, it is clear that The Mountain is a ruthless character. He is the direct cause of his brother, The Hound's, childhood trauma and the burn scars on his face.

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Game of Thrones is no stranger to brutality as gratuitous violence is a show staple, particularly in The Mountain's trial by combat duel against Oberyn Martell. Martell sought vengeance against The Mountain for his barbaric acts against his sister, Elia. Almost at death's door, Gregor admitted to these crimes: "I killed her... Then I smashed her head, in like this" right as he crushed Oberyn's skull with his bare hands.​​​​​​​

4 The Night King

Game of Thrones, The Night King

The Night King and the White Walker army are the stuff of old Westerosi legends, and were created by the Children of the Forest. The Night King's goal was to turn every living human into an undead zombie-like creature to join his growing army of the dead. He had no ulterior motives other than to trigger the Long Night to cover Westeros in an endless bleak winter and end all life.

He wholly lacks empathy, with no chance of redemption. In one heartbreaking scene, The Night King aims an ice javelin and brings down Daenerys' dragon, Viserion. He later resurrects Viserion as an undead dragon wight who then melts The Wall, allowing the White Walker army to cross into Westeros. The Night King was swiftly dealt with by Arya, with some fans complaining it was a disappointing end to a key villain.​​​​​​​

3 Joffrey Baratheon

Game of Thrones, Joffrey Baratheon

No other character is more despised than the boy king, Joffrey Baratheon. He is first seen as a petulant child with a hidden sadistic streak that gradually reveals itself as he ascends the throne. His first real act as King resulted in Ned Stark being beheaded, disregarding his promises to show mercy.

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Joffrey comes across as an unrepentant tyrant, abusing anyone he perceives to be weaker than him, like his uncle Tyrion. He even forced Sansa Stark to stare at her father's decapitated head on a spike. Game of Thrones fans celebrated Joffrey's demise, going down as one of the most gratifying deaths in the series.​​​​​​​

2 Cersei Lannister

Game of Thrones, Cersei Lannister

Cersei Lannister is a character that long-time Game of Thrones fans love to hate. She is devious, manipulative, and vindictive - all trademarks of a successful villain. Cersei's love for her children was unparalleled, though, as she made strides to secure the Lannisters as the most powerful House in Westeros.

As a mother, Cersei grew more ruthless as her children were murdered. To avenge her daughter Myrcella's death, Cersei poisoned Tyrene Sand, the daughter of the woman responsible for Myrcella's death as poetic justice, using the same methods - a daughter for a daughter. Cersei also used wildfire to blow up the Great Sept of Baelor, murdering thousands of innocent people. This barbaric act saw her crowned on the Iron Throne at the cost of her son Tommen's life. ​​​​​​​

1 Ramsay Bolton

Game of Thrones, Ramsay Bolton, Rickon Stark

House Bolton's sigil is literally an upside-down flayed man, aptly summarizing Ramsay Bolton's cruel and sadistic nature. He delighted in torturing others and playing mind games. He famously renamed Theon Greyjoy "Reek," and tortured him in many ways, like saying he had castrated Theon while eating a sausage in front of him.

Previously a bastard, Ramsay took full advantage of his newfound nobility. However, Ramsay's ambition knew no limits, and he later murdered his father once he had outgrown his usefulness. Ramsay initiated the legendary Battle of the Bastards against Jon Snow and forced Rickon Stark to strafe between his firing arrows. He purposefully missed his arrows until Rickon was heartbreakingly close to being saved by his half-brother Jon. Thankfully, Ramsay got his just deserts at the ravenous jaws of his not-so-loyal hunting dogs while locked in a cage with them.

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