Before the loot,
there was the lore.

Diablo’s creation myth begins with Anu, a being containing every possibility. When Anu cast out his darker nature, it became the seven-headed dragon Tathamet. Their struggle destroyed them both, but their remnants gave rise to the forces that would shape the universe: the High Heavens and the Burning Hells.

Angels and demons inherited that opposition. The angels’ ruling Angiris Council sought order; the seven Great Evils embodied different forms of corruption. Three became the Prime Evils: Mephisto, Lord of Hatred; Baal, Lord of Destruction; and Diablo, Lord of Terror. Their endless war is the Eternal Conflict. Humanity did not begin it, yet humanity would become its most fiercely contested prize.

The story begins with a cosmic war that neither side can decisively win.

Read more: Book of Lorath series overview · Creation mythology reference

The angel Inarius and the demon Lilith, Mephisto’s daughter, rebelled against the endless fighting. With other renegades, they used the Worldstone to create and conceal Sanctuary. Their descendants, the nephalem, combined angelic and demonic heritage and could surpass the power of either parent.

That potential frightened their creators. Lilith killed the renegade angels and demons to prevent them from destroying the children. Inarius banished her, then altered the Worldstone to weaken the nephalem across generations. Their descendants became ordinary humanity. This is why humans matter to both sides: beneath mortal fragility lies a power neither Heaven nor Hell can safely ignore.

Sanctuary was founded as a refuge, but fear and control fractured it from within.

Read more: Blizzard’s history of Sanctuary

Once Sanctuary was discovered, its people became targets of competing faiths. The Triune secretly served the Prime Evils, while Inarius led the Cathedral of Light. Lilith returned and helped awaken the farmer Uldyssian’s nephalem powers, seeking to use humanity against her enemies. His rebellion ultimately rejected the control of both camps. His sacrifice helped preserve humanity’s right to choose its own future.

Later, Hell’s internal revolt exiled the three Prime Evils into Sanctuary. Tyrael, the angel of Justice, gathered human mages into the Horadrim to hunt them. Their soulstones could imprison demonic essences. Diablo’s prison was hidden beneath what became Tristram’s cathedral; Baal’s imprisonment demanded the mage Tal Rasha’s own body. These fragile victories establish a recurring danger: containing an evil does not remove its ability to influence its keepers.

The Horadrim turn knowledge into a defence against evil—but their prisons are never simple solutions.

Read more: Sin War reference · Original Diablo manual · Tal Rasha reference

The original game brings that ancient history into a single frightened town. Diablo corrupts Archbishop Lazarus, drives King Leoric into madness and takes the king’s young son, Albrecht, as his host. Beneath the cathedral, layers of tombs and catacombs reveal how deeply Tristram has been infected. Leoric becomes the Skeleton King, and the Butcher turns a supposed rescue mission into a massacre.

A hero descends, defeats Diablo and finds Albrecht’s body. Hoping to contain the demon, the hero embeds the soulstone in his own forehead. Later lore identifies this warrior as Aidan, Leoric’s elder son. His attempted sacrifice becomes the next disaster: Diablo gradually overwhelms him. The saviour of Tristram leaves as the Dark Wanderer, carrying Terror towards the east.

Diablo’s most enduring horror is the possibility that a heroic sacrifice can become a doorway for evil.

Read more: Original game story · The Dark Wanderer’s history

New heroes follow the Dark Wanderer’s trail from the Rogue Encampment through Lut Gholein and the jungles of Kurast. His companion Marius is manipulated into freeing Baal from Tal Rasha’s prison. In Kurast, Mephisto has corrupted the Zakarum faith from within. The brothers reunite, and the Wanderer abandons his human disguise to reveal Diablo.

The heroes defeat Mephisto and Diablo, destroying their soulstones at the Hellforge. Baal survives and invades Mount Arreat. Although he is defeated in Lord of Destruction, he has already corrupted the Worldstone. Tyrael destroys it rather than allow that corruption to spread. Mount Arreat is devastated, and Sanctuary loses the artefact that had concealed and shaped it for ages. The victory saves the world from an immediate threat while leaving its future profoundly uncertain.

The destruction of the Worldstone changes the conditions of every story that follows.

Read more: Diablo II story · Lord of Destruction story

Diablo Immortal belongs between the second and third numbered games. The Worldstone is gone, but its scattered fragments retain immense, dangerous power. The story follows the struggle to contain those pieces and prevent their corruption from becoming another catastrophe.

Deckard Cain continues his work, and Westmarch offers a centre of human life amid the damage. This chapter matters to the wider timeline because it shows the aftermath of Lord of Destruction: ordinary people still have to survive after the grand battle is won. Sanctuary’s defenders inherit consequences, rather than a clean new beginning.

Chronological order differs from release order: Immortal bridges Diablo II and Diablo III.

Read more: Blizzard’s Immortal story overview

Twenty years after Diablo II, a falling star strikes Tristram Cathedral. It is Tyrael, who has surrendered his angelic existence to stand with humanity. The player’s hero discovers their own nephalem potential while working with Deckard Cain and his ward, Leah. Cain dies after an attack by Maghda, leaving Leah to carry his work forward.

The struggle against Belial and Azmodan centres on the Black Soulstone, which can hold the essences of all seven Great Evils. Leah’s mother, Adria, betrays the group and uses her daughter as Diablo’s vessel. Empowered by all seven Evils, Diablo assaults the High Heavens. The Nephalem defeats him, but the Black Soulstone survives. Once again, winning the final battle leaves behind the object that makes the next disaster possible.

Humanity’s forgotten power emerges—and proves capable of defending Heaven itself.

Read more: Diablo III campaign reference

Malthael, the former angel of Wisdom, returns as the Angel of Death and takes the Black Soulstone. His solution to the Eternal Conflict is horrifying: erase the demonic essence within humanity by destroying humanity itself. Westmarch’s streets become a killing ground as his reapers harvest souls.

The Nephalem pursues him with Tyrael and the surviving Horadrim, including Lorath Nahr. Adria is killed during the hunt. In the final battle, Malthael breaks the Black Soulstone and absorbs its power; his defeat releases the Evils it contained. Sanctuary survives, but is left devastated. The expansion also challenges the assumption that angels are naturally humanity’s protectors: a heavenly power can become just as terrifying as a demon when it denies people the right to exist.

Reaper of Souls leaves Diablo IV a wounded world and a much smaller margin for hope.

Read more: Reaper of Souls campaign reference · Blizzard on Malthael’s Westmarch

Decades later, Elias summons Lilith back into Sanctuary. The Wanderer becomes bound to her through her blood and joins Lorath, Donan and Neyrelle in pursuing her. Lilith offers liberation from the Eternal Conflict, but pursues it through manipulation and brutal sacrifice. Inarius leads the Cathedral of Light, convinced that fulfilling a prophecy will restore him to Heaven.

Their conflict destroys the family at the heart of Sanctuary. Inarius kills their son, Rathma, and is later killed by Lilith in Hell. Meanwhile, Mephisto, appearing as a bloodied wolf, steers the Wanderer against his daughter. Lilith intends to seize her father’s power. Neyrelle instead traps Mephisto in the soulstone, denying Lilith her prize. The Wanderer defeats Lilith, but Neyrelle departs alone with the stone. The immediate enemy falls; the Lord of Hatred’s influence travels on.

Lilith’s defeat resolves the pursuit of the Mother, while Neyrelle’s choice begins the next crisis.

Read more: Diablo IV campaign reference · Base campaign ending explained

The first expansion follows Neyrelle into Nahantu. Carrying Mephisto’s soulstone is destroying her peace and spreading corruption around her, even into the Spirit Realm. The Wanderer searches for her with the help of the Spiritborn mystic Eru, while the legacy of the revered prophet Akarat becomes central to the struggle.

Eru secretly bargains with Mephisto, hoping to spare Nahantu. He delivers the soulstone and Akarat’s physical remains to the demon. Mephisto gains the prophet’s body as his new vessel, turning a symbol of spiritual hope into a means of deception. The horror has shifted: Hatred can now approach people wearing the face of someone they trust. Neyrelle’s survival does not mean that the world has escaped the consequences of the bargain.

Mephisto’s most effective weapon is often trust turned against the people who offer it.

Read more: Vessel of Hatred ending reference

The second expansion takes the struggle to Skovos, where a prophet arrives in Temis and Mephisto’s influence spreads through devotion as well as demonic invasion. The campaign returns to the roots of humanity: the Pools of Creation, whose corruption would let Mephisto reshape humanity itself. Tyrael rejoins the struggle after Neyrelle calls for his help.

The confrontation closes the Age of Hatred campaign arc. A weapon fashioned from Lilith’s bone is used to banish Mephisto to the Void, rather than merely defeat another physical host. The distinction matters: the aim is to prevent the familiar cycle of death and re-formation. This is a conclusion to the campaign’s Mephisto storyline; it does not erase Sanctuary’s earlier tragedies or end the Eternal Conflict. The seasonal stories that follow should be read in their own narrative context.

The campaign returns to Sanctuary’s origins to confront the threat to humanity’s future.

Read more: Blizzard’s expansion overview · Campaign and ending reference

The current season revisits Diablo’s history through Waking Nightmares. Deckard Cain’s lost soul brings news of three dark wanderers. Their torment draws players back into echoes of battles with Diablo beneath Tristram Cathedral, Baal at Arreat Summit and Mephisto in the Durance of Hate.

Defeating those echoes yields Splinters of Evil. The player can carry a Prime Evil’s power, repeating the series’ uneasy relationship between borrowed strength and corruption. These encounters are presented as memories and nightmares, so they should not be treated as a simple reversal of every previous campaign death. For lore readers, the season connects familiar faces, places and relics to the history told above.

This season looks back through haunted memories; the main campaign and its historical events remain distinct.

Read more: Blizzard’s official season overview