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The earliest reference I can find to the Iron Cage is in Index Astartes I (released 2002), so the actual White Dwarf article must've been in the year or two before. The 1998 3rd edition Chaos Codex is extremely light on fluff and makes no mention of the battle.

The Imperial Fist fluff came in Index Astartes II, which was published a year later in 2003, so whilst it was definitely afterwards, as the intention of Index Astartes was to cover the Legions in chronological order, it is from the same period of fluff and was likely mapped out at a similar time.

Unless someone can find a notably earlier source than Index Astartes in the early 2000's, I will treat the fluff and contiguous and of essentially equal provenance.

For perspective, the 1990 Lost and the Damned book has the early form of the Horus Heresy in it (much retconned even by 3rd edition), and there is no mention of the Scouring at all in there. So the fluff is mid 90's at the earliest.


As such, we have two equally canonical interpretations of the Iron Cage incident- that the Iron Warriors were merely toying with their opponents and missed their opportunity to wipe them out when the Ultramarines arrived, and that the stubborness of the Fists demanded mutual destruction to eradicate with the Iron Warriors not prepared to make this final sacrifice.

Eitherway, aspects of the battle accounts that don't contradict should be accepted without issue, like Dorn wishing to put his entire Legion "through the pain glove". So it really isn't a fair representation of the strategic abilities of Dorn when he deliberately dropped his typical battle approach to put his Legion through "cleansing" pain. Still stupid mind.


If someone can provide a notably earlier source for the Iron Cage, then yes, that does change the situation somewhat.

 Haighus wrote:
Eitherway, aspects of the battle accounts that don't contradict should be accepted without issue, like Dorn wishing to put his entire Legion "through the pain glove".

That was only in the "pro-Fists" version. In the original "pro-Ion Warriors" version it was because Perturabo had taunted Dorn into attacking, and Dorn was too stubborn to withdraw when he was losing.

"Upon discovering that the Iron Warriors had taken refuge within the Eternal Fortress, Dorn declared that he and his Legion would travel to Sebastus IV and bring Perturabo back to Terra in an iron cage."

"The battle lasted another three weeks. The Imperial Fists' ammunition was expended and they fought individually in half flooded trenches with their combat knives, refusing to submit while they dug into the mud and used their fallen Battle-Brothers for cover. Dorn personally turned back a number of attacks. The Legion's Captains pleaded with their primarch to organize a breakout and retreat, but Dorn refused. Ever loyal, the Imperial Fists resigned to die fighting alongside their lord if necessary."

-Paraphrased from Index Astartes I

It looked into it and it looks like you are correct, the original "pro-Iron Warriors" version came out only a year before the Fists version, I honestly had thought it was longer than that. I don't however buy the argument that they "came out at the same time"... Index Astartes 1 came out a full year before Index Astartes 2.

w1zard wrote:
Index Astartes 1 came out a full year before Index Astartes 2.

Yes, but those were just compilations. The original WD articles for the IW and IF were published a mere 3 months apart (UK WD256 and 259 respectively), and both were written by Pete Haines. So they're obviously meant to be complementary, "two sides of the same story", not a retcon.

they both suck !

In all fairness, Dorn & Perturabo both won and lost. Neither died, but each were denied the "satisfaction" of ending each other.
If it was a bare handed (get it) fist fight, whichever one goes first would probably win, unless one of them rolled a 6.

Anyway, I'm not sure whom would be the champion.

 Duskweaver wrote:
Yes, but those were just compilations. The original WD articles for the IW and IF were published a mere 3 months apart (UK WD256 and 259 respectively), and both were written by Pete Haines. So they're obviously meant to be complementary, "two sides of the same story", not a retcon.

Then what do we do when we have "two sides of the same story" that directly contradict each other in certain areas?

w1zard wrote:

 Duskweaver wrote:
Yes, but those were just compilations. The original WD articles for the IW and IF were published a mere 3 months apart (UK WD256 and 259 respectively), and both were written by Pete Haines. So they're obviously meant to be complementary, "two sides of the same story", not a retcon.

Then what do we do when we have "two sides of the same story" that directly contradict each other in certain areas?

take both versions as half truth/half propaganda. I like it when GW leaves things ambiguous & makes you question the POV. Too much detail kinda ruins it.

Racerguy180 wrote:

w1zard wrote:

 Duskweaver wrote:
Yes, but those were just compilations. The original WD articles for the IW and IF were published a mere 3 months apart (UK WD256 and 259 respectively), and both were written by Pete Haines. So they're obviously meant to be complementary, "two sides of the same story", not a retcon.

Then what do we do when we have "two sides of the same story" that directly contradict each other in certain areas?

take both versions as half truth/half propaganda. I like it when GW leaves things ambiguous & makes you question the POV. Too much detail kinda ruins it.

Plus, the only bit that truly contradicts is whether the Iron Warriors could wipe out the Fists at any moment, but toyed with them, or whether they were not willing to make the final sacrifice to wipe out the Fists. The rest can easily be chalked up to information the other side is not privy to.

The weird bit, for me, is why the IW didn't wipe out the remaining Fists as soon as they got wind of the arriving Ultramarines- it generally takes some time to reach planetside from exiting the Warp in a system, and the IW had a picket of spacecraft to warn them. So why not make that final push as soon as they realised time was running out? That suggests, to me, that the IW could not finish the job as easily as their account states they could. They probably could do it with less casualties than the Fists account says they could though, but still too long/costly within the circumstances.

w1zard wrote:
Then what do we do when we have "two sides of the same story" that directly contradict each other in certain areas?

We sigh nostalgically and recall, misty-eyed, that that's how things were done back in 3rd edition. Or we roll our eyes and mutter darkly about how GW tried to make everything vague and contradictory (and sometimes over-the-top-mysterious and too-clever-for-its-own-good) in 3rd edition. It was controversial at the time. I've no doubt we will eventually get a BL novel that gives the Totally Official You Guys version of the story, and it will somehow manage to be much lamer than either of the current contradictory versions. And probably make both Perturabo and Dorn look like idiots dragged along by the Almighty Plot rather than actual characters with their own personalities and values.

 Haighus wrote:
The weird bit, for me, is why the IW didn't wipe out the remaining Fists as soon as they got wind of the arriving Ultramarines- it generally takes some time to reach planetside from exiting the Warp in a system, and the IW had a picket of spacecraft to warn them. So why not make that final push as soon as they realised time was running out? That suggests, to me, that the IW could not finish the job as easily as their account states they could. They probably could do it with less casualties than the Fists account says they could though, but still too long/costly within the circumstances.

Personally, I think the pro-Iron Warrior makes a lot more sense than the pro-Fists version. Even if the Fists were on the verge of losing, it still could have taken longer than a day to "finish them off" considering that the battle had raged almost two weeks by this point, plenty of time for the Ultramarines to deploy from space to the ground and stop the Iron Warriors. And the fact that the Iron Warriors had the power to blow the whole fortress at any given time seems to indicate to me that a "mutual annihilation" battle was never the objective, it was about inflicting disproportionate casualties on the Fists (or wiping them out if possible) and humiliating Dorn. Perturabo was just enjoying himself too much to bring himself to end it quickly, and when the ultramarines showed up unexpectedly it became "crap, too late, it's time to go".

As was also said before, the whole idea of Dorn "totally accepting the codex astartes, but he needed to put his men through a pointless meatgrinder first for some reason" is a little stupid. The pro-Iron Warrior version stacks up better with what we know about Perturabo's and Dorn's personalities, and Guilliman's political pragmatism. The pro-Fists version makes it seems like the Fists "totally meant to lose, serious guys".

w1zard wrote:

 Haighus wrote:
The weird bit, for me, is why the IW didn't wipe out the remaining Fists as soon as they got wind of the arriving Ultramarines- it generally takes some time to reach planetside from exiting the Warp in a system, and the IW had a picket of spacecraft to warn them. So why not make that final push as soon as they realised time was running out? That suggests, to me, that the IW could not finish the job as easily as their account states they could. They probably could do it with less casualties than the Fists account says they could though, but still too long/costly within the circumstances.

Personally, I think the pro-Iron Warrior makes a lot more sense than the pro-Fists version. Even if the Fists were on the verge of losing, it still could have taken longer than a day to "finish them off" considering that the battle had raged almost two weeks by this point, plenty of time for the Ultramarines to deploy from space to the ground and stop the Iron Warriors. And the fact that the Iron Warriors had the power to blow the whole fortress at any given time seems to indicate to me that a "mutual annihilation" battle was never the objective, it was about inflicting disproportionate casualties on the Fists (or wiping them out if possible) and humiliating Dorn. Perturabo was just enjoying himself too much to bring himself to end it quickly, and when the ultramarines showed up unexpectedly it became "crap, too late, it's time to go".

As was also said before, the whole idea of Dorn "totally accepting the codex astartes, but he needed to put his men through a pointless meatgrinder first for some reason" is a little stupid. The pro-Iron Warrior version stacks up better with what we know about Perturabo's and Dorn's personalities, and Guilliman's political pragmatism. The pro-Fists version makes it seems like the Fists "totally meant to lose, serious guys".

But why did they not leave a rearguard to blow the fortress anyway? The whole battle involved pockets of Iron Warriors left to die as rearguards in the Index Astartes IW account, and Perturabo absolutely would expect troops under his command to carry out such an action. The two IA accounts also have no mention of said explosives in the first place- the only explosives mentioned are used to blow up the remote silos.

The Ultramarines should take more than a day to arrive from the Warp entry point- typically in 40k this seems to take at least a few days, commonly weeks. Ground-to-orbit communication was (deliberately) impaired through the silo blasts kicking debris into the atmosphere, but Perturabo (along with most of the Primarchs) is the kind of commander to create some kind of contingency to allow his fleet to warn him of approaching enemies. Indeed, he somehow knew of the approach of the Ultramarines early enough to evacuate, and this would have required coordination with the fleet. So why not detonate the possible explosives/otherwise wipe out the remaining Fists prior to their arrival? It is all a bit odd.

We know the Imperial Fists survive with at least 6000 Marines, although probably not as many as 8000 Marines*. They started the Horus Heresy with approximately 100000, so over the entire Heresy and Scouring, that is some pretty hefty losses, especially considering that there would still be recruitment from worlds over the 20 odd years where possible. We know around 20000 didn't make it back from the events around Phall alone, and several thousand were likely scattered across the Imperium in garrisons, such as the garrisons in the Manachea Commonwealth. However, the Fists would have suffered huge casualties at Terra, so could easily have entered the Scouring with a total strength in the low ten thousands. Considering this, the numbers surviving the Iron Cage are not that low.

I absolutely agree Dorn's reasoning here is bonkers, although it does make a kind of in-character sense within the context of a Legion that regularly does something as bizarre as using the Pain glove.


*Based on there being five confirmed Second Founding IF successors plus the IFs themselves (Excoriators, Soul Drinkers, Crimson Fists, Black Templars, Knights Exemplar), and one other Chapter known to be a member of the Last Wall protocol who could be a Second or Third founding Chapter (Iron Knights). However, as the Executioners are not a member of the protocol (confirmed Third Founding Chapter), that strongly suggests that the Iron Knights are a Second Founding Chapter too. As the Second Founding occurred immediately after the Iron Cage incident according to current background, this prevents significant recruitment from bolstering the IF numbers. Therefore, the Legion strength is probably between 6 and 8 thousand Marines following the Iron Cage.

In a one on one fight Perty but in a war Dorn.

 Haighus wrote:
The two IA accounts also have no mention of said explosives in the first place- the only explosives mentioned are used to blow up the remote silos.

I thought the Iron Warriors version also mentioned that the entire fortress was rigged for self-destruct as "insurance".

 Haighus wrote:
The Ultramarines should take more than a day to arrive from the Warp entry point- typically in 40k this seems to take at least a few days, commonly weeks. Ground-to-orbit communication was (deliberately) impaired through the silo blasts kicking debris into the atmosphere, but Perturabo (along with most of the Primarchs) is the kind of commander to create some kind of contingency to allow his fleet to warn him of approaching enemies. Indeed, he somehow knew of the approach of the Ultramarines early enough to evacuate, and this would have required coordination with the fleet. So why not detonate the possible explosives/otherwise wipe out the remaining Fists prior to their arrival? It is all a bit odd.

Sure, sometimes a fleet warps in and the defenders get advanced notice while the fleet coasts towards its destination from the outer halo... and sometimes that takes awhile, but not all of the time. I'm just not understanding how you can't see a situation where it is possible that the Iron Warriors had enough time to withdraw, but not enough time to finish off the Fists.

Secondly, it is possible that the Ultramarines rescued the surviving Fists immediately after they arrived, and right as they started to engage Perturabo's rearguard, making blowing up the fortress pointless (the Iron Warriors wanted to kill Fists, not Ultramarines). My point is that the timeline given to us is vague enough so that this kind of thing is possible.

"After three solar weeks and six days, the Ultramarines finally intervened despite the Imperial Fists' protests, driving the Iron Warriors off the world with a combined orbital and ground assault. Unable to defeat two full Legions that had combined their forces, Perturabo concentrated on denying the Imperial Fists' ability to withdraw intact and preventing them from collecting their dead and wounded. Over 400 Loyalist Battle-Brothers' bodies were never recovered by the Legion, and this failure still ranks as a terrible dishonour for the Imperial Fists and all of their Successor Chapters."

-Paraphrased from IA

It definitely sounds like Perturabo's withdrawal wasn't as "clean" as you seem to think. He may not have had the opportunity to trigger the fortresses' self-destruct without devastating his own legion in the process.

 Haighus wrote:
We know the Imperial Fists survive with at least 6000 Marines, although probably not as many as 8000 Marines*. They started the Horus Heresy with approximately 100000, so over the entire Heresy and Scouring, that is some pretty hefty losses, especially considering that there would still be recruitment from worlds over the 20 odd years where possible. We know around 20000 didn't make it back from the events around Phall alone, and several thousand were likely scattered across the Imperium in garrisons, such as the garrisons in the Manachea Commonwealth. However, the Fists would have suffered huge casualties at Terra, so could easily have entered the Scouring with a total strength in the low ten thousands. Considering this, the numbers surviving the Iron Cage are not that low.

No, we don't have exact numbers for how many Fists went into the Iron Cage, but we do know that it was the majority of the remaining legion. As you said, only roughly 6,000 walk out alive and at LEAST 500 die in the iron cage (in all likelihood probably many times that).

Even if, say 15,000 Fists walked into the iron cage, that is 60% casualties which is absolutely devastating. For reference, in a modern battle, anything over 15% casualties is considered "unacceptable losses" by most first world armies. To put it in another perspective, the British Army during WW1 numbered roughly 2 million men... The battle of the Somme which is one of the bloodiest battles in history saw a total of roughly 450,000 British soldiers killed which is roughly 25% casualties over 140 days. The Fists suffered over TWICE as much casualties (proportionately) and possibly even more (if they walked into the iron cage with more than 15,000 marines) over a period of 27 days.

As much as I would like to apply real life casualty figures to 40k, its pointless to do that. The numbers involved in these things and lost in the battles are often arbitrary, or chosen because big numbers sound better.

I dunno if this is something unique to that universe, or a actual military convention but I know that in battletech, in various sourcebooks etc, if a unit takes 60% casualties in a battle (I'm talking the fluff not the table top) assuming this is an actual thing then, strategicly speaking the Imperial fists where destroyed in that conflict.

 VictorVonTzeentch wrote:
As much as I would like to apply real life casualty figures to 40k, its pointless to do that. The numbers involved in these things and lost in the battles are often arbitrary, or chosen because big numbers sound better.

True, but that was in response to a poster who was making the claim that 6,000 surviving Fists means that their defeat at the Iron Cage wasn't that bad.

BrianDavion wrote:
I dunno if this is something unique to that universe, or a actual military convention but I know that in battletech, in various sourcebooks etc, if a unit takes 60% casualties in a battle (I'm talking the fluff not the table top) assuming this is an actual thing then, strategicly speaking the Imperial fists where destroyed in that conflict.

Yeah but "destroyed" from a military readiness standpoint is different than "destroyed" as in wiped out to a man. They are two different things. Technically, the Imperial Fists weren't destroyed because they adopted the codex astartes immediately after and had more then enough men to form a full chapter, which would put them back at operational readiness.

I will give the Fists this... they survived a situation that was meant to kill them all. The hung in there and fought like bastards and survived against all odds. But, equally lets call a spade a spade... Perturabo bested Dorn in that battle. He completely manipulated Dorn's emotional state and goaded him into a strategic blunder which was then exacerbated by Dorn's stubbornness and refusal to retreat. It very nearly cost Dorn his life along with the lives of the remaining Imperial Fists. Who the more brilliant strategist between the two is as irrelevant as the fact that Napoleon was a better General than his opposition at Waterloo... he still lost. And I don't buy that garbage about Dorn meaning to lose or meaning to get his legion decimated by walking into the Iron Cage, it is objectively idiotic writing and an attempt to placate Fist fanboys.

Objectively idiotic or not that's the canon. 40k is full of it. Like the current lore on the Emperor fighting Horus.

It seems as more likely to me Dorn walked into a trap to attempt to address survivors guilt. It's not so much that he did it to convince his legion to accept the codex, but that in the aftermath he had a "ohh my god, what did I almost do? Maybe there's some wisdom in this codex thing!"

BrianDavion wrote:
It seems as more likely to me Dorn walked into a trap to attempt to address survivors guilt...

Sure, if you want to spin it like that, fine. Perturabo still took advantage of it.

w1zard wrote:

BrianDavion wrote:
It seems as more likely to me Dorn walked into a trap to attempt to address survivors guilt...

Sure, if you want to spin it like that, fine. Perturabo still took advantage of it.

absolutely, Perty won that fight. I won't deny it, nor will most people. they would however argue it's a hard thing to gauge how they'd normally do vs one another as Dorn wasn't in his right mind. I think the big question is, "Did Dorn ever really recover, or did he continue to basicly push to get killed?" It makes his fate, IMHO much more intreasting, if he continued trying to find ways to get HIMSELF killed`

BrianDavion wrote:

w1zard wrote:

BrianDavion wrote:
It seems as more likely to me Dorn walked into a trap to attempt to address survivors guilt...

Sure, if you want to spin it like that, fine. Perturabo still took advantage of it.

absolutely, Perty won that fight. I won't deny it, nor will most people. they would however argue it's a hard thing to gauge how they'd normally do vs one another as Dorn wasn't in his right mind. I think the big question is, "Did Dorn ever really recover, or did he continue to basicly push to get killed?" It makes his fate, IMHO much more intreasting, if he continued trying to find ways to get HIMSELF killed`

It would explain how basic Chaos Marines killed him if he wanted them to considering the sheer badassery of Primarchs at fighting. Except Lorgar.

pm713 wrote:
...It would explain how basic Chaos Marines killed him if he wanted them to considering the sheer badassery of Primarchs at fighting. Except Lorgar.

Except Lorgar got pretty badass when he turned to chaos to the point that even Angron remarked about his improved combat skills.

I thought Dorn ended up getting swamped by dozens of CSM in close quarters? All it takes is for one lucky blow to end it and Dorn wasn't known for being the best duelist. I don't understand how you cannot imagine a group of regular marines overwhelming a primarch in a CQC situation when the likes of Sigismund and Loken exist... not all standard marines are mooks.

over all I like the idea Dorn was seeking death to the point he got himself into a situation he shouldn;t have. sure anyone can be swarmmed by large numbers of lesser people. but Dorn shouldn't have got himself in such a position. if he's effectively trying to get himself killed cause survivor's guilt, it makes it make some more sense and IMHO makes him a more tragic character

Y'all are talking about things that have little to do with 1 on 1 combat.

Pert wins. Handily.

 EmpNortonII wrote:
Y'all are talking about things that have little to do with 1 on 1 combat.

Pert wins. Handily.

prove it.

Seriously, we keep hearing that Dorn supposidvly sucked at close combat, but I've seen little real evidance for that, he's not talked about as being one of the greats, but nor is Perty

cody.d. wrote:
It would be like saying the Lion was a better fighter because he sucker punched Wolfboy after he stopped fighting and laughed at the ridiculousness of their original argument.

Sadly Perty and Lord Adorable have never had a proper fight either of them have been prepared for. In addition, it's like any comic book fight. The one who wins is who the author wants to win.

But my money is on Bou.

Lion is a better fighter. Russ threw the first sucker punch. Lion threw the last. Difference is only one got knocked out. Lion also completley destroys Kurze 2 out of 3 times and would have have done so another time if guilliman wasnt with him during the 2v1. Because the Lion was constantly blocking hits ment for Guilliman, he was more of a handicap than a help and resulted in Kurze escaping. Kurze was also regarded as one of the better fighters amongst the primarchs

BrianDavion wrote:
Seriously, we keep hearing that Dorn supposidvly sucked at close combat, but I've seen little real evidance for that, he's not talked about as being one of the greats, but nor is Perty

It is not that Dorn SUCKED in close combat, merely that aside from his fight with Alpharius he was just never seen doing it or training for it. Alpharius was also not known for his skill in dueling either. Whereas Perturabo went toe to toe with daemon Fulgrim and smacked him around. For reference daemon Fulgrim killed Ferrus Manus and almost killed Guilliman so that makes Perturabo better than or equal to two primarchs by default and probably more.

I wouldn't compare Perturabo with the likes of Angron, Kurze, or Lion, but he is definitely at least middle of the pack when it comes to personal 1v1 combat.

BrianDavion wrote:

 EmpNortonII wrote:
Y'all are talking about things that have little to do with 1 on 1 combat.

Pert wins. Handily.

prove it.

Seriously, we keep hearing that Dorn supposidvly sucked at close combat, but I've seen little real evidance for that, he's not talked about as being one of the greats, but nor is Perty

I mean, how can you prove anything like that? For what it is worth, Perturabo with forgebreaker in 30k stomps Dorn and only really can't kill Russ and Horus, with coin flips for a couple others. Represented in the fluff by whomping Fulgrim, as mentioned earlier

BrianDavion wrote:

prove it.

Seriously, we keep hearing that Dorn supposidvly sucked at close combat, but I've seen little real evidance for that, he's not talked about as being one of the greats, but nor is Perty

In Angel Exterminatus, Fulgrim muses that Perturabo is very strong, perhaps the strongest of all his brothers. While not true IMO, one of the premiere duelist Primarchs speaking well of Perturabo's might holds some water.

What does Dorn have? His only win against a Primarch is against the midget of the group which he barely won, Curze nearly killed him with his bare hands, and he even happens to be one of the single worst duelists of the Primarchs on the tabletop.

BrianDavion wrote:

w1zard wrote:

BrianDavion wrote:
It seems as more likely to me Dorn walked into a trap to attempt to address survivors guilt...

Sure, if you want to spin it like that, fine. Perturabo still took advantage of it.

absolutely, Perty won that fight. I won't deny it, nor will most people. they would however argue it's a hard thing to gauge how they'd normally do vs one another as Dorn wasn't in his right mind. I think the big question is, "Did Dorn ever really recover, or did he continue to basicly push to get killed?" It makes his fate, IMHO much more intreasting, if he continued trying to find ways to get HIMSELF killed`

I don't think Perty won that fight in any meaningful sense. . Perty wanted Dorn broken and dead.

Either

(a)Dorn was a broken man nuts with grief, who may have known full well it was a trap ,wanted to die, Roboute convinced him to live

(b)Dorn had a clear head and achieved the outcome he wanted- using Perts trap as a painglove to purge his legion.

Either way he emerged stronger as a person from the Cage, with enough marines to forge 6 chapters (that we know of) in the second founding, one of which was Sigismund's legion. More successors than any of the Isstvaan survivor legions managed, more than the Wolves, more than the Scars (including successors that we know of).

This is after casualties taken bearing the brunt of the battle of Terra and doubtless inflicting disproportionate casualties on the traitors there and after the fists had successfully razed the part of the Iron Warriors who fortified Olympia and its environs Not a single IW escaped that battle and it took 10 years to do- indicating a significant portion of the legion had to be killed and rooted out.

The official kill tally for the iron warriors at the cage is 400 fists. Until it is revised and covered in depth, that is pathetic. We can assume that the fists lost far more men but

It wasn't enough to affect the battle readiness of the fists
It wasnt enough to demoralise the fists
Dorn lived and had renewed clarity.

 Duskweaver wrote:
Has Dorn ever shown any ability to read other people and take advantage of their psychological weaknesses, though?

The only book I've read where his perspective is even touched upon is Praetorian of Dorn, and that seems to suggest its less a matter of Dorn being bad at it as it is him not having patience for it. When Alpharius tries to play with him by addressing him 'as' three separate marines with different degrees of elaborate armour, Dorn refuses to play along, deciding the first one he saw is Alpharius and addressing him so - to chastise him for his stupid-elaborate family assassination plan that ultimately caused more long-term problems than a quick siege would have, he accuses Alpharius of mistaking confusion for subterfuge. Dorn demonstrates what he means in their final battle in the book: appearing to fall into Alpharius' trap, turning in instead of out to catch a showy spear strike in the shoulder, and carving into Alpharius with Storm's Teeth. He didn't fall for any of Alpharius' clever lures, he came because if he did, Alpharius would appear himself to deliver the killing blow.

We see this elsewhere in hints: when asked if maybe an Astartes Legion could beat his fortress on Terra, he explicitly says 'not if they were lead by Perturabo.' At the council of Nikea, he's the only one to argue that Librarians should be allowed but Magnus should be censured anyway. When he returns from his revenge tour to find Guiliman splitting up the Legions he accuses him of betraying their father's will to feed his own ego. People see this as a long-standing characterization of Dorn being blunt and ill-equipped with the social nicities, but interpreted through what we see of him in Praetorian and he comes to focus as a very different person: one who very easily identifies his brothers differences and is very critical of them, often to the point of cruelty.

If he and Perty were to fight, Dorn would definitely want to turn his brother's insecurities to his advantage: approach with confidence, appear to have it crumble as he takes a beating, then drive in a killing blow when Perty starts to gloat. That's what I see as his endgame, anyway; everything else depends largely on when and what circumstances surround the fight - Perty, as stated before, goes all out all the time with his best armour and weapons, whereas Dorn is more likely of the two to change up his gear depending on what he expects to fight. This is compounded by the fact that for a lot of his post-Heresy life, Dorn seems to be trying to commit suicide by heretic.