"No plan survives first contact with the enemy."
-Moltke the Eldar
Time for some lore/strategy Jeopardy: we know the answers, but what are the questions?
We know the outcomes of what happened to each of the loyal Legions during the opening moves of the Horus Heresy. What I would like to explore in this thread are Horus's plans for dealing with each loyalist legion.
The trick is is to rewind things pre-Istvaan and try to see things through Horus's eyes. You don't know what sort of list your opponent will bring. You don't know exactly how the terrain will be set up. You don't know how the dice will roll. You can guess, and you can predict, and you can plan. And that planning part is what I us to have fun delving into.
These types of topics are the most fun to explore, IMO, and I would imagine are one of the delights of writing for BL/FW. So let's explore and have fun!
I Dark Angels
A good one to start with to demonstrate what I mean. We know that Thramas happens....but did Horus look at an Org chart and say "hmmm. Let's sick Curze and the Night Lords on the Lion!" or did that campaign develop due to battlefield* conditions?
My memory of the first few HH novels on the DA is fuzzy, but if I recall, the Lion was doing his thing when he found out about the Heresy and then sent a splinter fleet to investigate and find out if it was true, correct? In which case it would mean that Horus.....apparently didn't have a plan for the Dark Angels? No grand trap they are lured into, no elaborate ruse, no alpha strike, etc....
Again, in hindsight we know that Caliban rebels and that whole storyline essentially knocks the DA out for a while, thus make 40k DA what it distinctively is compared to 30k DA....but no one knows that's happening, nor could they have known, let alone could Horus have put that piece on the chessboard as he laid out his plans.
So how did Horus plan to deal with the Lion and the I Legion?
See "Istvaan Situation" below.
*battle space, you know what I mean
V White Scars
This is the trickiest of all. Part of what has made Chris Wraight's HH novels on the Scars so deliciously awesome is that element of unknown. The Outrider angle. No one knew what to expect from the V Legion or their reliably elusive Primarch.
What makes it especially fun is that the White Scars were so good at doing their own thing, Horus could not have been sure where to find them, let alone plan to deal with them in any way.
Was Horus so sure of his relationship with the Khan, and that his ruse of saying Russ was the real traitor at Alaxxes would work, that he simply expected them the V to join his cause?
That's why it makes the most sense that the Alpha Legion were sent after them, most likely with the mandate to Find, Stall, Confuse, Neutralize.
Don't forget that Mortarion on Prospero, and then Morty + Eidolon/III Legion in Pathway to Heaven happens much deeper into the timeline of the Heresy. We're talking about Horus's plans pre-Istvaan.
VI Space Wolves
The Battle of Prospero is obvious here, but where this gets intriguing is what Horus really expected from it. Clearly his intention was to drive Magnus to his cause while hurting what is indisputably one of the biggest threats to his rebellion. But what did he really want to happen?
Did he want the SW to lose, thus crushing them entirely?
Did he want them to win so handily (especially with Titans, Custodes, etc...) that it would absolutely guarantee the Magnus came to his side?
...but what if Russ succeeded so well he actually killed Magnus? Then the entire point of Prospero seems strange.
There's more going on under the surface with this one.
I am a bit unclear on the exact timelines and details* of this, so I am grouping it all together and mentioning things at a macro scale.
This part makes sense. The Alpha Legion were standing by, ready to finish off the SW after Prospero. What makes this a smart move is that the Alpha Legion are probably the perfect group to do this. There is no better force for effortlessly working murky situations and adapting to nebulous (get it? Alaxxes Nebula?) situations. If the SW were seriously hurt, the AL could pounce and attempt to finish them off. If the SW came out of Prospero particularly well, then the AL could confuse, misdirect, harass, and otherwise with their heads, all the more so if the SW were not aware of the greater heresy. It's quite the shrewd move on Horus' part.
...however, one thing that stands out to me is the forces dedicated to Yarant. 7x Legions were used to crush 3 at Istvaan, yet a single Legion is expected to deal with one of the fiercest, most independent ones that happens to specialize in "executing" other Legions? Even with the AL's propensity for not fighting fair, it seems like quite the bold gambit.
*I know Abaddon was somehow involved in this as well, but I don't know the specifics
VII Imperial Fists
The VII were responsible for the Sol System. That much we know. Dorn was also the Emperor's Praetorian, so there was a very high likelihood that Dorn would be the last Primarch to be dealt with. However, what if Ferrus turned traitor? Or what if Dorn was chosen to lead the Istvaan attack instead? This is where things get interesting.
Grouping this into the "Istvaan Situation"
IX Blood Angels
The Battle of Signus Prime. This is one of the more "obvious" ones. Horus and Sanguinius were confidantes and about as close as two Primarchs could get. Sangy would have obeyed a direct order from the Warmaster anyways, but inflecting it with a bit of a personal request that he take his entire Legion really put things over the edge.
The brilliance of this move is that from the moment the IX set sail*, Horus had succeeded. Best case scenario, Sanguinius and his entire Legion now join Horus's cause OR are wiped out completely (Horus might actually have preferred the latter). Worst case scenario, even if the IX somehow fought flawlessly and did not take a single casualty, they are so far out of the way and cut off that they are effectively removed from the fight for the first round. And of course Horus was a fan of mathhammer and figured the averages so even the middle result--the IX survive but are bloodied, demoralized, and disoriented--is just as acceptable. It's a win-win for Horus.
*yea its in space. You know what I mean.
X Iron Hands =
We know what happened at Istvaan.....but don't forget that Horus originally attempted to sway Ferrus to his cause, using Fulgrim's bromance with FM as the fulcrum (hmmm....Fulgrim/fulcrum? coincidental spelling?)
We also know that Horus lamented Ferrus' absence in his cabinet. He is forced to work with the likes of Mortarion and Fulgrim, not to mention Curze and Angron. So clearly Horus had plans for Ferrus, both as an ally and as an opponent.
If Ferrus turned, what sorts of timetables would Horus had been working with? What sorts of maneuvers or activities would he attempted? Would he have taken even more time to build up before attacking Terra? Or would he have done just the opposite and gone for the throat even quicker? Perhaps sending Ferrus ahead to start harassing the Sol System right away*, distracting other loyalist forces, not allowing Dorn a chance to prepare the way he really would want to, and so on.
If Ferrus did not turn, but did not lead the attack on Istvaan, what sorts of contingencies would Horus have up his sleeve?
XIII Ultramarines =
Pearl Harbor in space. Fairly straightforward and beautiful in its simplicity. Hamstring the largest legion in the opening moments in a decisive betrayal from a brother who has enough resentment built up to really make it work. And how about we kick it off by disguising the whole thing has a "teambuilding exercise" between two legions who have some bad blood going on? Check. Next task.
I mean really, this one is so good it looks easy in hindsight. Like so many of his other moves in this list, the beauty of it is that it's a win-win for Horus. Best case scenario Guilliman is killed and the XIII is crippled beyond concern. Worst case scenario, the UM turtle up in the Ultramar sector since they believe they are under attack by a single vengeful foe (thus missing out on the true intentions).
How much of the Shadow Crusade was Horus's grand plan and how much of it was a request by Lorgar that Horus went along with? Reading Betrayer, I get the impression that it was more of the latter.
Did Horus know that Vulkan and his sons would be the ones to respond on Istvaan?
If not, how did he plan--if he had specific plans at all--to deal with them?
I find the lack of any information here intriguing. Did Horus not even bother attempting to turn Vulkan? If not....than why? Etc....
XIX Raven Guard
Same as with the Salamanders: did Horus know for a fact that they would be the ones to respond to Istvaan?
If he did not, especially considering the falling out Corax and Horus had earlier on, you'd think that Horus would consider Corax a particular threat based on his predilections for unconventional warfare. We can clearly see just how much Horus relied on the Alpha Legion for that very reason. One would think that Horus would prioritize an opposing force with (somewhat) similar capabilities.
Special: The Istvaan Situation
Do we know that Horus absolutely knew what Legions/forces would be committed to Istvaan?
It's another juicier topic than it seems and if we don't, involves some deductive reasoning.
Legions Horus had discrete, concrete plans for:
- VI Space Wolves
- IX Blood Angels
- XIII Ultramarines
- **V White Scars** --> grouping them in here because it seems certain that they were so far out there on there own, both physically and mentaliy, that it would have been extremely unlikely that they would be part of the Retribution force heading to Istvaan
Which would then leave:
- I Dark Angels
- VII Imperial Fists
- X Iron Hands
- XVIII Salamanders
- XIX Raven Guard
Of those, the Iron Hands could have turned traitor, otherwise Horus would undoubtedly have special plans for Ferrus. If Ferrus could not lead the Retribution force, whether due to switching teams or being otherwise incapacitated, would the Imperial Fists have left Sol to join in? What if Dorn had led the assault on Istvaan? Or the Lion?
Imagine if the Dark Angels, Imperial Fists, and Salamanders attacked.
How much does that impact the course of the war? How successful is Istvaan in comparison to how it actually turned out?
Interesting food for thought.