Summary
Sugar, spice, and everything nice, that and the genetically engineered power granted by the Emperor himself. Thus the sons of the Emperor were born inWarhammer 40,000.Twenty superior and ‘perfect’ men who were intended to be superhuman generals would embark with the emperor upon the Great Crusade and unite the scattered worlds of the Imperium and bring mankind into a new ‘Golden Age’.
EachWarhammer 40kPrimarch shared attributes such as strength, charisma, intellect, and constitution and was supposedly immortal. Each also embodied a particular skill that set them apart from the others, as intended by the Emperor. Strength is a hard indicator to measure inthe tabletop board game realmofWarhammer. Apart from brute strength or martial prowess, there are many other aspects to observe as entire battles and wars have been won on more than strength alone.

Updated October 31st, 2024 by Jacob Buchalter:The Primarchs in the Warhammer 40k setting are such absurdly ridiculous walls of muscle. Each one of the Emperor’s Children has their own over-the-top backstory, gimmick, and supernatural abilities. Each of these children ended up on a different planet in a different corner of the galaxy, and as such they all grew up with entirely different foundations, abilities, and more. Because of this, and because of the fact that they’re so far above the standard ‘human’ by our definition, it can be difficult to compare the Primarchs to each other in regard to their overall power. However, while difficult, it’s not impossible, and thankfully they have gone against each other enough throughout the official Warhammer 40k media as well as all connected (and canon) other media that we can give a pretty decent picture of how each Primarch stacks up against each other.
2nd

11th
Records Redacted
Getting these two out of the way as early as possible, let’s briefly talk about the two ‘Lost Primarchs’ and their Chapters which seem to have been completely purged alongside the Primarchs and all records of them in the annals of the Imperium’s history. The most interesting part about these two Primarchs being completely erased from history is that it was done before the Horus Heresy.
One would assume that, after seeing that two of the 20+ Primarch’s names had been stricken from the history books, they were likely part of the Horus Heresy, but that’s actually not the case. While it’s unclear exactly what these two Primarchs did to receive such an all-encompassing punishment, there are throwaway lines and passages across the vast number ofWarhammer 40kbooks that allude to some things. For example, in a story calledA Thousand Sons(which obviously is centered around Magnus the Red and his Thousand Sons), both Magnus and Mortarion briefly mention these erased Primarchs and seem to imply the event that caused their erasure happened the last time that so many of the Emperor’s sons were all gathered on the same planet.

14th
Word Bearers
Armour of the Word Artificer Armour & The Illuminarum Sceptre-Maul
Lorgar is the most widely ‘hated’ of all the Primarchs, both in-universe and out of it. He’s a fanatical zealot of the highest degree, and this was during a time when the Imperium of Man was not at all the heavily religious empire it is in 40K. Granted, Lorgar grew up in a world, Colchis, that had religion embedded in its very foundation, so this does make sense.
Still, this guy is basically the first Primarch to fall to Chaos, the main perpetrator behind Horus falling to Chaos, and is all-around a very sociopathic person, switching from overflowing charisma to violent rage in an instant and without warning. Before the Horus Heresy, Lorgar was easily the physically weakest of all the Primarchs. Obviously, this still put him leagues above a mortal man, but the difference between him and his brothers was clear. During the Horus Heresy, due to the influence of the Chaos Gods, Lorgar grew a lot more powerful in both the physical and psychic sense. Still, even then, there aren’t many tales of his one-on-one victories against his fellow Primarchs. It is worth noting that he’s basically the only ‘unaffiliated’ Chaos Primarch, and this does give him some unique strengths and freedom compared to the other Daemon Princes (though Abadon does represent this ‘unaffiliated faction’ of Chaos much more than Lorgar does).

4th
Iron Hands
The Forgebreaker Thunder Hammer
Ferrus Manus (AKA ‘The Gorgon) was a Primarch that sadly didn’t get a lot of ‘screentime’ in mostWarhammermedia. This is mostly due to the sad fact that Manus died during the events of the Horus Heresy. To be more precise, Ferrus was the most renowned blacksmith alive, able to use his ‘living metal’ arms to mold and shape metal barehanded (no Smithing Hammer required). And, like most artisans, Ferrus Manus was a perfectionist, always trying out some new armor or weapon he designed in battle so that he could re-tune and perfect it later.
As a fighter, not much is really said about him, other than little mentions here or there. His metal arms have made many speculate he might’ve been the physically strongest Primarch, but that still ultimately falls to Vulkan, as multiple Primarchs have backed up this claim. In general, Ferrus Manus was well known and respected, but ultimately hisbiggest contribution toWarhammer’sloreis being decapitated by Fulgrim to show him fully giving himself to Chaos. Well, that and the fact that Perturabo still uses Manus’legendary melee weapon, the Forgebreaker hammer, as his weapon of choice.

13th
Death Guard (Nurgle)
The Barbaran Plate Power Armour & The Silence Battle Sycthe
Mortarion is probably one of the more well-known Primarchs overall. He’s absolutely not one of the most iconic, but mostWarhammer 40kfans at least know his name and his dedication to the Chaos God Nurgle. For reference, anyone who hasput a lot of time intoWarhammer 40k: Darktidehas had a lot of exposure to the minions of Nurgle. Mortarion is another one of those who joined Horus in the Horus Heresy, as he let his long-held grudge against the Emperor for ‘stealing the kill’ of his adoptive father on Barbarus fester for too long. In the current age of 40k, Mortarion is still the most powerful champion of Nurgle and is basically the primary representation of the Chaos God in general. And Nurgle, for those who are unaware, is the Chaos God who has the most ‘love’ for their minions, as can be seen byhow the faction functions inTotal War: Warhammer III.
As a fighter, Mortarion is the very definition of a ‘Tank’. He’s bulky, slow, powerful, and dense. While he doesn’t provide a ton of offensive power using his gaunt frame, Mortarion almost always tanks damage to a degree where he quite literally tires his opponents out. This is yet another way in which Mortarion echoes his Chaos God, as Nurgle is all about being unmoving, unchanging, and unrelenting.

20th (possibly 1st)
Traitor (maybe)

Dead (apparently)
Alpha Legion (Opposed to Chaos)
The Pythian Scales Artificer Armour & Sarrisanata Double-Bladed Spear
There are Primarchs that specialize in stealth warfare, Primarchs that specialize in defensive battles of attrition, and then there’s Alpharius Omegon and their battles of espionage and deception. To be blunt, while the name Alpharius Omegon is meant to describe ‘one’ of twenty Primarchs, it is, in fact, two separate identical twins, one named Alpharius, and the other Omegon. These twins run the XXth Legion of the Imperium of Man, and there is very little truly known about them.
They barely ever appear in their true form, they always attack from multiple sides with a myriad of appearances, and most people aren’t even aware they got on the bad side of the XXth Legion until the battle is basically over. Alpharius and Omegon are some of the bigger fan-favorite Primarchs since the concept of a Primarch who is unknown even amongst their own Legion is so incredibly unique. While Alpharius is the ‘public face’ of the Alpha Legion, the two can be swapped at any time without anyone recognizing the difference. And, as a final little fact, even their own Legion alters their appearances to look as similar to Alpharius and Omegon as possible so that the twins can pass unknown and undetected even among their most trusted brothers. It’s also worth stating that, at least in the 41st millennium, Alpharius is widely regarded to be dead at the hands of Rogal Dorn, but with all the mystery surrounding Alpharius and Omegon this death could easily be retconned at some point.

17th
Alive
World Eaters (Khorne)
The Samni’arius Daemonsword, Gorefather and Gorechild Chainaxes, & The Bitcher’s Nails
Funnily enough, though many would consider Angron to be one of the stronger Primarchs, given his unending fury and penchant for battle, the guy has been beaten by his loyalist brothers more than he’s beaten others. As it turns out,strength for an individual or even an entire factiondoesn’t boil down to just raw physical strength. In fact, even during his ‘introduction’ when the Emperor first discovers Angron on his home planet, Angron has lost the rebellion he had been fightingsince his days as a Gladiator. And, oddly enough, the Emperor doesn’t help Angron win his war and doesn’t even let Angron die with his ‘brothers and sisters’ like he wanted to.

Overall, Angronis a perfect warrior of Khorne, relishing in battle, violence, and fury. But, power isn’t just about raw fighting strength, and Angron is lacking in all categories not related to raw emotion or combat potential. He has no talent for tactics, no skill in leadership, and literally has tech in his brain that causes him immense pain whenever he’s not feeling anger.
15th

White Scars
The White Tiger Dao Sabre & His Sojutsu Pattern Voidbike
Out of all the many Primarchs of the Emperor, only one seems to have been blessed with the gift of ‘common sense’, and it’s Jaghatai Khan. The Legion Jaghatai leads, the White Scars, were obviously based on the Mongol Empire, and it worked wonders for them.This Space Marine chapter excelled in one thing, speed, and no one else even came close. As for Jaghatai Khan as an individual fighter, he was around the middle of the pack. Of course that isn’t including his speed,as the man was so fastthat one time, while killing Orks, he killed them so fast that even Orks stopped having fun fighting him.
Many of his Primarch brothers respected him, but not many directly feared him. That said, Jaghatai, when he does get to be in books or other media, always seems to make sensible decisions and outsmart those who try and trick him. In fact, he’s the only Primarch who listened to both sides during the early stages of the Horus Heresy and even told the Traitor Legions that he understood where they were coming from.
5th
Emperor’s Children (Slaanesh)
The Blade of the Laer Daemonblade & The Firebrand Volkite Charger
Primarch of the traitorous Legion of the Emperor’s Children, a name that became a mockery of the Imperium after his betrayal, Fulgrim is best remembered as the favored Daemon Prince of Slaanesh. To achieve this, he slaughtered his most trusted brother, Ferrus Manus, with decapitation. Fulgrim is an excellent warrior who is perhaps one of the only turn-cloak Primarchs to express remorse for the massacre of his battle brothers on Istvaan V.
Though Fulgrim’s abilities are usually a topic of hot debate among the fanbase, given how depraved and twisted he is, remember that Fulgrim and his Legion pursued ‘perfection’ before they became turncoats. And now, as a giant snake-like Daemon Prince, Fulgrim is still dedicated to perfection, but his definition of the word has changed, and nothing about him representsthe idea of a ‘hero’that would’ve described him before the Horus Heresy.
18th
Unknown
Raven Guard
The Panoply of the Raven Lord Lightning Talons & The Korvidine Pinions Flight Pack
With several monikers and titles such as the ‘Raven Lord’ and ‘Liberator’, Corvus was always considered striking in his appearances and on the field of battle. As Primarch of the Raven Guard legion of Space Marines, Corvus was blessed with the ability to move about unnoticed and slip away from his enemies with ease,making him an unrivaled assassin.
It was these skills and his undying loyalty to the Imperium that allowed him (and several other Raven Guard Astartes) to survive the massacre at Istvaan V when so many others did not. Though devastated by the betrayal and loss of so many battle brothers, Corvus did not give up and actually got permission from the Emperor of Mankind to try and remake his Legion using the same or similar technology the Emperor used to make the Primarchs. Ultimately, however, this was in vain, as the attempt failed, and Corvus had to ‘put down’ what he had made.
Then, as a sort of exile, he ventured into the Warp in an attempt to take vengeance on his traitorous Primarch brothers. In the few times Corvus Corax has been seen since then, he’s basically become a Warp Entity that people love to say is a Daemon. He can now turn into the shadows themselves, a flock of ravens, a whirlwind of shadow, and a few other things. And, while some may say this proves he’s a Daemon, it more proves that his extended time in the Warp has completely removed him from the ascended human he used to be (whether this is a good or bad thing remains to be seen).
9th
Thousand Sons (Tzenntch)
The Blade of Magnus & His Crown of the Crimson King
The Primarch of the Thousand Sons, Magnus the Red, honestly has one of the most tragic stories out of all the Emperor’s children. One of,if not the strongest Psyker alive(second only to the Emperor at his peak), Magnus and his Legion were the mostpowerful Psyker fightersin all of the Imperium. And, in all their pursuits, Magnus even managed to create a Utopia for himself and his people on a planet called Prospero. Sadly, this put him at odds with the Emperor more often than not, as Magnus seemed to relish in his Warp abilities while the Emperor ultimately wanted to break everyone away from Chaos and the warp entirely.
Then, through events during and before the Horus Heresy, Magnus not only lost Prospero, but he unintentionally ruined the Emperor’s long-term web-way system plan and also fell prey to Tzeentch, the Chaos God of Change and Sorcery. Now a Daemon Prince of Tzeentch (and honestly one of themore powerful Daemon Princes), Magnus literally bends the fabric of space and time wherever he walks and destroys the minds of all those nearby just by being around them.