How We Ranked Them
This list ranks betrayals by one thing: how much each one destroyed, going only by what the canon records. It counts down from #8 to #1. In some entries the champion is the one betrayed and in others the traitor, and either way it is the damage that gets ranked.
#8. Riven
Riven, the exiled swordmaster, was a war orphan who pledged her strength to Noxus, the empire that raised her on one of its farms, and she saw her bond with her fellow soldiers as unbreakable. During the invasion of Ionia, a land that would not kneel to the empire, her unit was sent to escort another warband. Its leader, Emystan, had hired an alchymist from Zaun to test a new weapon, and the jars on his wagons, in her biography's words, "had no purpose on any battlefield she could imagine."
In a rainstorm, with mud pouring down the hillsides, Riven and her warriors were stranded with the wagons, and Ionian fighters attacked. Riven called to Emystan for support.
The only answer she received was a flaming arrow, fired out from the ridgeline, and Riven understood this was no longer a war to expand the borders of Noxus. It was to be a complete annihilation of the enemy, no matter the cost. The wagon was hit straight on. Instinctively, Riven drew her sword, but it was too late to protect anyone but herself. Chemical fire burst from the ruptured containers, and screams filled the night—both Ionian and Noxian falling victim to an agonizing, gruesome death.
— Riven - Biography
From Riven - Biography
The magic of her runic sword, a gift from Boram Darkwill, the ruler of Noxus at the time, kept the poison off her. It was too late to protect anyone else, and she watched her own soldiers burn beside the Ionians they had been fighting.
For Riven, memories of the hours that followed come only in fragments, and nightmares. She bound her wounds. She mourned the dead. But, most of all, she came to hate the sword that saved her life.
From Riven's biography
She broke the blade to cut her last tie to the empire and wandered Ionia in exile. When Noxus finally sent soldiers after her, she surrendered to the charge of desertion rather than let more Ionian blood be shed on her account.
Her story opens the list because the damage stayed inside one ambush: one convoy, and the soldiers of both armies who stood near it.
#7. Swain
Swain, who rules Noxus today as its Grand General, began as a young noble who uncovered the Black Rose, a secret cabal plotting against Darkwill, and personally executed its most prominent members, his own parents among them.
The cabal survived him. LeBlanc, the cabal's matron and #4 on this list, had manipulated Swain into exposing it, and she let herself appear to be executed with the rest. Then she went to Darkwill herself. In her own biography:
After promising him the secrets to extend his life, LeBlanc slowly poisoned Darkwill’s mind, even as she empowered him. Under his rule, the Noxian reverence of strength became something far more sinister, and together they ensured Swain’s legend would end in disgrace on the battlefields of Ionia.
From LeBlanc's biography
In Ionia, Darkwill pulled whole warbands off the front to hunt for anything that might extend a mortal life, and Swain was left without the soldiers to fight.
Finally, at the Battle of the Placidium, after luring the local militia into what should have been a trap, Swain’s warhost was overrun. His veterans were routed, and Swain was gravely wounded, his knee shattered, Ionian blades cleaving through his left arm.
— Swain - Biography
From Swain - Biography
Lying near death, Swain saw the truth in a raven's eye: the Black Rose "had betrayed him to what should have been his death." He lived, but the army threw him out for his "failure," and he spent years as a cripple before he took the empire from Darkwill in a single night.
Swain sits above Riven because the flaming arrow burned one convoy, while the Black Rose's betrayal broke the whole warhost, the army Swain led into Ionia. Riven's biography records her soldiers dying in agony and Swain's says only that his veterans were routed, so the record shows more dead in her ambush. An army broken in the field is still a bigger loss than one convoy.
#6. Zed
Zed, the founder of the Order of Shadow, grew up in the temple of the Kinkou, Ionia's order of monks who keep the balance between the spirit and material realms. Great Master Kusho, the order's leader, took him in as a boy, and Zed grew up beside Kusho's son Shen like a brother.
The war split them. Zed looked inside a black box the order kept from all but its masters, and its shadow magic fed his contempt for the weak. When Kusho refused to strike the invaders with every means the Kinkou had, Zed left, raised his own warriors, and came back with them for the box. Kusho met him at the temple, laid his weapons at Zed's feet and begged him to give up the shadows.
Moments later, Zed emerged back onto the temple steps. In one hand, he grasped the box—and in the other, his freshly bloodied blade. The Kinkou, frozen with shock, fell in droves as Zed’s warriors cut them down. He then claimed the temple for himself, establishing his Order of Shadow, and began training his acolytes in the ways of darkness.
— Zed - Biography
From Zed - Biography
Zed's biography never shows the blow. Shen's does:
Worst of all, Shen’s father had been slain by the man he once saw as kin.
From Shen's biography
Shen was away when it happened. He came home to the survivors of the coup, led what was left of the Kinkou to safety in the mountains and took up his father's spirit blade. Zed kept the temple as the seat of his new order.
Zed ranks above Swain because the Black Rose broke one army in the field, while Zed's coup killed the Kinkou's leader and cut its members down in droves, and the few who lived lost their temple.
#5. Hecarim
Hecarim, who now rides as a spectral fusion of knight and warhorse, was a lieutenant of the Iron Order, a brotherhood of knights sworn to defend their king's lands. He had risen to lead it by leaving his own commander to die in battle, and the knights, not knowing, swore themselves to him.
Kalista, the king's niece and most trusted general, once saved the king from an assassin, but the deflected blade was poisoned and cut the queen. Kalista sailed to the Blessed Isles, a hidden island realm whose people were said to know the secrets of eternal life, and came back too late. The queen was dead, and the king called Kalista a traitor.
Hecarim talked her into guiding the fleet back so the king could hear the truth from the masters of Helia, the isles' capital, himself. They refused him. Death, they insisted, was final.
Enraged, the king ordered Kalista to kill them, but she refused, and Hecarim smiled as he made the decision that would damn him for eternity. He drove a spear through Kalista’s back, and ordered his knights to ransack the city, looting its vaults of arcane treasures.
— Hecarim - Biography
From Hecarim - Biography
Kalista's own biography says she asked him for help first:
She refused, and called on Hecarim to stand with her… but instead he drove his spear through her armored back.
The Iron Order joined him in this treachery, piercing Kalista’s body a dozen times more as she fell.
From Kalista's biography
Her loyal warriors died fighting his knights, and the Iron Order emptied the city's vaults. In that chaos a custodian led the king to the Waters of Life, where he meant to bring his queen back (the story at #2). The Ruination, the disaster that followed, caught Hecarim by surprise and fused him with his horse.
Hecarim ranks above Zed because Zed's coup took one temple, while Hecarim's spear turned an order of knights on its own general and set them loose on a city.
#4. LeBlanc
LeBlanc, the matron of the Black Rose, has a biography that keeps even her identity vague, perhaps "unknown even to herself." Her spot comes from legends that many of the cabal's initiates have uncovered: a pale sorceress who served in the inner circle of Mordekaiser, the Iron Revenant, a warlord raised from the dead in iron armor who built an empire on necromancy.
Under him, "entire generations perished." He raised the Immortal Bastion, a fortress at the center of his empire and the source of his power. The Noxii tribes, the barbarians who later built their own empire in the bastion's shadow, rose against him, and the sorceress turned on him from inside.
Uniquely skilled among the revenant’s inner circle before she betrayed him, the sorceress pledged to neutralize the source of his power, the Immortal Bastion, cutting him off from the well of death that fueled his nightmarish empire.
— LeBlanc - Biography
From LeBlanc - Biography
Mordekaiser's biography tells the same fall from his side:
The Iron Revenant was defeated, surprisingly, by an alliance of the Noxii tribes, and betrayal from within his own inner circle. This hidden cabal managed to sever the anchors of his soul from his armor, and sealed the empty iron shell away in a secret place.
From Mordekaiser's biography
That ended his empire among the living, though Mordekaiser's biography says he had planned for his fall and meant to forge a new empire from the souls of his dead. LeBlanc's biography also leaves open whether she is "still the same pale sorceress who betrayed the Iron Revenant, or merely one of countless hollow reflections."
LeBlanc ranks above Hecarim because his knights sacked one city, while this betrayal ended an empire. Hecarim's betrayal has deaths on the record, Kalista's and her warriors', and this one has none, but the fall of an empire still outweighs the sack of a city.
#3. Lissandra
Lissandra, the Ice Witch, was one of three sisters, with Avarosa and Serylda, whose great alliance of Iceborn warriors and troll kings brought the ancient Freljord to heel. A primal god's claws took her sight, and she learned to walk in dreams instead.
In those dreams she came to see the Void, the emptiness beneath the world, as more than an ending. Without telling her sisters, she struck a deal for all three with the Watchers, god-like beings of the Void: near-immortality, in exchange for preparing Runeterra for the Void's coming. When her sisters learned of it, Avarosa argued that "the only thing worse than death was servitude," and they marched their warriors to Lissandra's fortress to end it.
The Void erupted into the mortal world in the far north, and with it, Lissandra’s hidden allegiance to the Watchers became undeniable. In that moment, her only choices were to let all the world be consumed, or to give up what she cared for most—Lissandra sacrificed her sisters and the allies they had gathered, entombing the Watchers beneath a glacial barrier of magical ice that could never be melted.
— Lissandra - Biography
The one account of that day left in her citadel's libraries, written by her most trusted scribe, gives the scale:
The ground split open, swallowing thousands of warriors into the abyss beneath it, before the first of the dread things heaved itself up into existence.
From The Legend of the Frozen Watchers
To seal the rift, she drew on all the magic around her, her allies' included, and buried the Watchers in True Ice, a magical ice that can never melt. Her sisters died in it. Afterwards she seized every record of what had happened and had anyone hailed as either sister reborn "quietly killed."
Lissandra ranks above LeBlanc because the sorceress's betrayal toppled one ruler, who had planned for his fall, while Lissandra's cost thousands of warriors and both of her sisters, and ended the alliance that ruled the Freljord.
#2. Thresh
Thresh, the Chain Warden, was a lowly warden on the Blessed Isles in life, keeping the vaults of dangerous artifacts beneath Helia for an order devoted to gathering and guarding arcane knowledge. His brethren had noted his cruelty and shunned him, and years alone in the dark left him bitter about the recognition he never got.
His chance came with the same invasion that ended Kalista's life. The king wanted the Waters of Life for his dead queen, and Thresh led him there willingly, into a catacomb that only the order's most senior members had ever been allowed to enter.
Now, with the king’s greatest warriors at his back, Thresh laughed as the guardians of that sacred place were cut down before him. Finally, he believed, he would get what he had long deserved. Only those who were there could say what truly occurred when the king lowered the lifeless corpse of his wife into the Waters, but the aftermath would shake the whole of Runeterra.
— Thresh - Biography
From Thresh - Biography
What followed was the Ruination, the cataclysm that turned the Blessed Isles into the Shadow Isles:
A catastrophic blastwave of dark energy surged outward, engulfing Helia and spreading rapidly across the rest of the Blessed Isles, and the white mist that had once protected them turned black and predatory. Every living thing in its path perished in an instant, and yet their spirits could not move on, caught in a horrifying new existence somewhere between life and death.
From Thresh's biography
Thresh was among the first it claimed, and he reveled in it. He came back as the specter who tears out the souls of those he kills and keeps them in his lantern, and the Black Mist, the deadly fog the blast left behind, still reaches past the isles' shores.
Thresh ranks above Lissandra because the world survived her betrayal, while the Ruination killed every living thing on the Blessed Isles and kept their spirits from moving on. Her bargain came closer to ending everything, since her biography says her other choice was "to let all the world be consumed," but the world came through and the Blessed Isles did not.
#1. Xerath
Xerath, who is now a being of pure arcane energy, was born a nameless slave in Shurima, the desert empire. As a boy he helped Azir, the emperor's least-favored son, read a hard old text. They grew as close as brothers, and Azir gave him his name, which means "one who shares."
Xerath killed to put Azir on the throne, burning Azir's own father to ash. Once crowned, Azir would not end slavery and told Xerath to remember his place. Xerath talked him into the Ascension, the sun rite that had remade the brothers Nasus and Renekton, Shurima's greatest heroes, and weakened the seal on a beast of living fire to keep both brothers busy that day. At the last moment on the dais, Azir freed him:
The emperor turned to Xerath and told him that he was now a free man. He and all Shurima’s slaves were now released from their bonds of servitude. He embraced Xerath before naming him his eternal brother.
From Xerath's biography
His plan rested on Azir's death, and he went through with it. With "a roar of anger and grief combined," he blasted Azir off the dais and watched through tears as his friend burned.
But the power of the ritual was not his to take, and the consequences of his betrayal of Azir were devastating. The unbound power of the sun all but destroyed Shurima, sundering its temples and bringing ruination upon the city. Azir’s people were consumed in a terrifying conflagration as the desert rose up to claim the city.
— Xerath - Biography
From Xerath - Biography
The sun disc fell, and "an empire built by generations of emperors was undone in a single day." Renekton then wrestled Xerath into the Tomb of Emperors and bade his brother Nasus seal them inside, where Xerath spent centuries poisoning his mind.
Xerath ranks above Thresh because the Ruination destroyed the Blessed Isles, while Xerath's betrayal destroyed an empire in one day. Thresh's ruin has lasted longer: the Black Mist still spreads, and Shurima has risen again with Azir. But the canon names Xerath's betrayal as the cause of Shurima's fall, while Thresh only led the king to the Waters of Life, and what happened there, his biography says, "only those who were there could say."
Your Verdict
Whose story do you think holds the greatest betrayal in the lore?
