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Warhammer 40k Mortarion - Meet the Death Guard Primarch

Our full, odour-free guide to all Warhammer 40k Mortarion, Daemon Primarch of the Death Guard - including Horus Heresy lore, datasheets, and models

Warhammer 40k Mortarion Primarch guide - Games Workshop artwork showing the Daemon Primarch Mortarion in the 41st Millennium during the Plague Wars

Warhammer 40k may be grim and dark, but it’s hard to find any Primarch grimmer than Mortarion. Bereft of any remaining humanity and always accompanied by his Death Guard – a lethal legion of Chaos Space Marines – Mortarion is a name to strike fear into hearts across the universe of the far future. Renowned for being surrounded by noxious fumes and dread diseases, Mortarion and the Death Guard are implacable opponents able to march inexorably forward, forever grinding through any foe.

Though once a relentless warrior of the Imperium, Warhammer 40k Mortarion joined the Horus Heresy, becoming one of the great generals of the Warmaster’s rebellion. He fell further than most, however, becoming tainted by Chaos and eventually ascending – so to speak – to serve the ruinous powers as a vast, winged Daemon Prince. To the current day, in the Warhammer 40k setting, he still fights against the Imperium – though more often he fights when and where Nurgle wills it.

Mortarion is a semi-tragic figure in the Warhammer 40k universe. Many decisions he made were not entirely his own and – were circumstances only slightly different – he might have stood alongside the Emperor throughout the civil war.

Here’s our guide to Warhammer 40k Mortarion, the Primarch of the plague-ridden Death Guard:

Warhammer 40k Mortarion Primarch guide - Games Workshop artwork showing the young Primarch Mortarion on Barbarus

Mortarion pre-heresy – his beginnings

Whisked away from safety by the forces of Chaos, the pre-Heresy Mortarion was deposited on the toxic planet of Barbarus. Many worlds that homed Primarchs were harsh, but Barbarus was unusually cruel, the only safe place to live being the troughs of its deep valleys. Any attempt to climb out led into choking poisonous fog, leading all humans to be corralled in these brief areas of respite.

Mortarion, however, was not raised by the normal humans who inhabited this poisonous planet. He was instead found by the Warlord of Barbarus, a member of a psychic xenos species who had enslaved the planet’s human inhabitants.

As Mortarion grew, he was eternally tested by his adoptive father, who discovered Mortarion was resistant to the planet’s fog, along with other physical enhancements that made him unique on the planet. One day, after seeing the torture and punishments the Warlord meted out on his slaves, Mortarion fled, heading to the valleys to eventually become accepted by the human populace.

There, Mortarion began to raise a rebellion to take the planet from their Xenos rulers once and for all. Teaching them all he knew of the ways of war, the young Primarch helped Barbarus’ people build weapons and trained them to strike back at their masters. Though they were successful at first, his troops were unable to ascend the mountains to wreak their final revenge.

Warhammer 40k Mortarion Primarch guide - Games Workshop artwork from the cover of Black Library novel Buried Dagger, showing Mortarion and Callas Typhon

Gathering the hardiest of his rebel fighters, Mortarion trained and equipped them further, turning them into living weapons for the final challenge. Armed with respirators that would help them survive, he led his newly-named Death Guard to victory over the majority of the Xenos slavers.

Alas, one of their foes still remained, on the highest peak, where the most deadly poison lurked: the Warlord of Barbarus, Mortarion’s former guardian and torturer. It was at this time that a golden stranger appeared, challenging Mortarion to climb alone to the final fortress to slay the Warlord of Barbarus, ending the war once and for all.

Beset by fumes and with his armour corroding around him, Mortarion climbed until he faced his adoptive father in single combat. The last thing Mortarion saw as he collapsed to the ground was the golden stranger stepping forth, striking the Warlord down with one swing.

This stranger revealed himself to be the Emperor of Mankind, and Mortarion to be his long-lost son. Reunited at last, Mortarion was given command of the 14th legion of Space Marines – a legion then called the Dusk Raiders, but which he swiftly renamed ‘Death Guard’, after his former guerrilla brotherhood.

Warhammer 40k Mortarion Primarch guide - Games Workshop artwork showing Mortarion fighting Jaghatai Khan of the White Scars during the Horus Heresy

Mortarion in the Horus Heresy (and afterwards)

Unlike many legions, the pre-Heresy Death Guard shunned psykers wherever possible due to Mortarion’s distaste of anything tainted by the Warp. In addition, Mortarion was isolated from his fellow Primarchs, befriending only Horus Lupercal himself and Konrad Curze, the Night Haunter. Though close to Horus, Mortarion was not the first to join the heresy – and nearly did not side with his insurrectionist brothers at all.

It was only through manipulation that Mortarion turned to serve Chaos. Horus played on Mortarion’s hatred of tyrants and of the Warp, convincing him that the Emperor’s use of the Warp – along with his position as supreme ruler over humanity – had led him to become nothing more than another sorcerous aberration that Mortarion needed to end.

After coming face to face with a Daemon, Mortarion slew it using his own latent psychic powers, leading him to realise that the Emperor had lied to him about the nature of the Warp. Instead of fearing this power, Mortarion now became determined to master it. It was this that led him to study forbidden knowledge, becoming conversant with Chaos artifacts and powers that slowly twisted him into something both more and less than a Primarch.

Though he studied and used the powers of Chaos, he still managed to keep himself separate from them – until a dark pact (schemed by his First Captain, Callas ‘Typhus’ Typhon) caused him to submit to the Chaos God Nurgle.

Warhammer 40k Mortarion Primarch guide - Games Workshop photo showing the new mortarion model at the head of a Death Guard army

On the way to Terra to begin the final assault of the Horus Heresy, the Death Guard fleet became lost in the Warp. During this time, a plague swept through the Death Guard, slowly twisting them into mutants and threatening to torture them all for eternity unless they openly embraced the dark powers of Chaos.

Though he hated the idea, the promise of enhanced power and endurance – and the drive to protect his legion – caused Mortarion to accept this bargain. From that moment, Mortarion and the Death Guard ceased to follow their own will, instead becoming little more than tools of Chaos.

After the eventual defeat of Horus, Mortarion led his legion to the Plague Planet, deep within the Eye of Terror. There, he experimented widely with disease, gaining the favour of Nurgle, and was eventually granted all the power of a fully fledged Daemon Prince.

Warhammer 40k Mortarion Primarch guide - Games Workshop photo showing the Horus Heresy 30k Forge World Mortarion model

This power and alignment with Chaos mean that Mortarion has survived the intervening ten thousand years between the Horus Heresy and the current time period in Warhammer 40k.

In the 41st Millennium, Mortarion became embroiled in the events surrounding the return of Ultramarines Primarch Roboute Guilliman, sending deadly plagues and a massive invasion force to take Ultramar – a colossal attack known as the Plague Wars.

Though that offensive was eventually defeated – forcing Mortarion to face the displeasure of Grandfather Nurgle – the Death Lord lives on, forever plotting, on behalf of his Chaos God patron, to bring the Imperium to ruin.

Warhammer 40k Mortarion Primarch guide - Games Workshop photo showing the new 40k Mortarion model fully painted at the head of Death Guard army

The Mortarion Model in Warhammer 40k

Mortarion is one of those rare Warhammer Primarchs that has three tabletop models. The first is a Forge World exclusive for use in Horus Heresy 30k battles, showing the Primarch before he fell to Chaos and became a bit daemon-y. The second is a shrouded death-like figure designed for the Epic game system, dating from 1992.

The third model is the one we’ll focus on here, as it’s the Mortarion model you’re most likely to encounter playing Warhammer 40k, or if you’re building your own Death Guard army. One of the largest models in the game (that’s not some form of Titan), Mortarion floats above the battlefield on giant, tattered wings.

His face is shrouded by a rebreather and his vastly swollen armour is pitted with corrosion. There’s no doubt that the Mortarion model depicts a mighty champion of Nurgle – one who has fallen far from his days fighting for the Imperium.

Mortarion comes armed with several weapons and means of attack. The Lantern, a ranged pistol, deals damage to everything in -between the Primarch and his target. Silence, his colossal scythe, is a Plague Weapon (those re-roll ones to wound, Death Guard fans) with two modes – able to either deal double-strength hits to tough foes, or sweep away swathes of lesser units, picking up extra attacks as it goes.

Warhammer 40k Mortarion Primarch guide - Games Workshop photo showing the Warhammer 40k model Mortarion, Daemon Primarch of Nurgle

He’s even accompanied into battle by daemonic, censer-carrying ‘Attendants’ who aren’t shy about getting involved in the action, using their claws and teeth to damage enemies in melee.

Combine that roster of damage-output with several abilities that enhance Mortarion’s survival – such as Disgustingly Resilient, a 4+ invulnerable save, extra Warlord Traits, and buffs that improve nearby Death Guard marines – and Mortarion exemplifies everything that’s wonderful (and horrible) about his legion.

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If you’re facing off against Mortarion, you’ll want him dead as soon as possible. Good luck making sure he bites the dust, though, as he has a nasty tendency to stick around far longer than you hoped.

A challenge to fight as well as to paint, this huge model is a true collector’s item and one that can easily become the centrepiece of your Death Guard collection.

If you need more Mortarion in your life, our Death Guard guide will give you all the noxious gases you’ll ever want. Check out the other Ruinous Powers with our guide to all the Warhammer 40k chaos factions or embrace the Imperium with our comprehensive guide to Space Marines.