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Now we're pretty much diverting from the subject at hand.

I still see no massive reason why a SM chapter couldn't be founded on cadia.

No we're not. You asked why, we gave a great many reasons. They don't do it, because Cadia needs all the bodies they can get.

What I'm trying to say here is not getting the answer you wanted("It's totally doable, go for it!") doesn't make it "off topic".

If you want some kind of Chapter that somehow or another recruits from Cadia, taking the same kind of individual that is earmarked for the Kasrkin, be aware that it won't be a very popular one amongst fluff fans.

If you want a Chapter that actually has workable fluff and a concept that people will like--be aware you're going to have to put some work into it.

Kanluwen wrote:No we're not. You asked why, we gave a great many reasons. They don't do it, because Cadia needs all the bodies they can get.

Well we were "discussing" what PDF's are like. The SM would still be fighting on cadia, I don't think it'd be any kind of disadvantage.

Lappie wrote:

iproxtaco wrote:When the vast majority is what Kanluwen described, then yeah, you can generalize.

It's only the vast majority because there arne so many planets in the Imperium, and most arn't under constant threat of attack, still no reason to presume a PDF can't be relatively well trained.

No one's presuming anything. It's a generalization, because generally, the vast majority are what Kanluwen described them to be.

Lappie wrote:

Kanluwen wrote:No we're not. You asked why, we gave a great many reasons. They don't do it, because Cadia needs all the bodies they can get.

Well we were "discussing" what PDF's are like. The SM would still be fighting on cadia, I don't think it'd be any kind of disadvantage.

We were discussing what PDF's were like because the 'PDF' of Cadia was brought up. No PDF exists, it's the Interior Guard--which is not the same entity.

However if you can't see the disadvantage of taking Cadia's best and brightest that would be going into the Kasrkin's numbers and HOPING they don't die during the initiation and augmentation process, I'm not quite sure I can help you see why that's a risk that is silly to take.

It would only be one year that there would be a big drain on intake to kasrkin. After that there would be the kasrkin AND a new chapter of eager space marines all with a great fighting tradition and reputation behind them.

Then they would have to recruit more to keep the ranks up, starting the process again.

Chapters aren't built in a year.

They're built up over decades.

The Imperium doesn't just decide one day "Hey guys, we're gonna have new Space Marines!" and suddenly, they have new Space Marines.
It's a long process, which is another reason it's ridiculous compared to just keeping the Kasrkin.

And quite frankly...who needs "Cadian Marines" when you have the Kasrkin. Hardcore, soldiers for life who are pretty much 40k's equivalent of the Spartan-II program?

Yeah. Not seeing a reason to get rid of Kasrkin for Cadian Marines.

Yeah but it's be a much smaller number.

Hundreds of aspirants a year, with maybe a quarter of that able to actually accept the surgical/genetic portion in addition to surviving.

That's still a lot of potential Shock Troops or Kasrkin going down the drain.

Kanluwen wrote:Chapters aren't built in a year.

They're built up over decades.

The Imperium doesn't just decide one day "Hey guys, we're gonna have new Space Marines!" and suddenly, they have new Space Marines.
It's a long process, which is another reason it's ridiculous compared to just keeping the Kasrkin.

And quite frankly...who needs "Cadian Marines" when you have the Kasrkin. Hardcore, soldiers for life who are pretty much 40k's equivalent of the Spartan-II program?

Yeah. Not seeing a reason to get rid of Kasrkin for Cadian Marines.

I never said anything about totally getting rid of the kasrkin


Automatically Appended Next Post:

Kanluwen wrote:Hundreds of aspirants a year, with maybe a quarter of that able to actually accept the surgical/genetic portion in addition to surviving.

That's still a lot of potential Shock Troops or Kasrkin going down the drain.

still not alot compared the the overall number in the cadian military system

Kanluwen wrote:However if you can't see the disadvantage of taking Cadia's best and brightest that would be going into the Kasrkin's numbers and HOPING they don't die during the initiation and augmentation process, I'm not quite sure I can help you see why that's a risk that is silly to take.

Given that a 1000 man SM Chapter hits harder than a 1000 man Kasrkin Company, it's not a silly risk to take.

What is silly is the fact this thread is still going, despite the fact that you already made the post that should've been the period at the end of this thread's sentence, ie: the bit about the Eye of Terror book saying that Marines DON'T recruit from Cadia. Since the OP was asking if a Chapter could recruit from Cadia, this answered the question pretty solidly. While it might make sense for them to do so, GW has laid down the law: it don't happen.

Not a lot of wiggle room to put a SM Chapter in there.

Equivalent to the Spartan II program? Close, but not quite.

Lappie wrote:It would only be one year that there would be a big drain on intake to kasrkin. After that there would be the kasrkin AND a new chapter of eager space marines all with a great fighting tradition and reputation behind them.

There are a number of reasons against as have been discussed but lets continue on your patha dn try and sort out a good fluff reason/s.

It also worh remembering that setting up a new Chapter is no small undertaking and will take time to do - maybe decades to put everytihg in place - from the logistical equipment and infrastructure to the geeneseed.

You could write something that follows the devestation of the 13th Black Crusade and how the Imperium deicdes to set up a new Chapter on Cadia - after all sometimes the Imperiums descions are not always wise or made of obvious reasons (or at least don't appear so).

Perhaps the rumoured Astartes Praeses donate thei geneseed to this undertaking - perhaps the founding goes well - or perhaps it does not. Pretty much all of the big name Chapters are involved so again they could be moved to petition for a Chapter (personally I doubt it- but you could write someting along these lines.........)

There is a potential story here and it could be told............some will enjoy some will not.........

squidhills wrote:

Kanluwen wrote:However if you can't see the disadvantage of taking Cadia's best and brightest that would be going into the Kasrkin's numbers and HOPING they don't die during the initiation and augmentation process, I'm not quite sure I can help you see why that's a risk that is silly to take.

Given that a 1000 man SM Chapter hits harder than a 1000 man Kasrkin Company, it's not a silly risk to take.

Given that a 1000 man Marine Chapter won't ever be fielded all at one place, while a Kasrkin Company would(and has)...I'd say the issue of who hits harder is moot.
To give an idea, however, the Honour Roll for the 13th Black Crusade lists 19 Kasrkin Companies "commended for Conspicuous Gallantry".
The Order of Battle given at the outset of the campaign in White Dwarf 281?
486 Kasrkin Companies.
Think about that for a moment.
That's 486,000 Kasrkin. 486,000 men all trained to the standard of the Stormtroopers, with them receiving their training after having already served time within the Shock Troops proper.

That's 486,000 men I'd want serving under my command.

What is silly is the fact this thread is still going, despite the fact that you already made the post that should've been the period at the end of this thread's sentence, ie: the bit about the Eye of Terror book saying that Marines DON'T recruit from Cadia. Since the OP was asking if a Chapter could recruit from Cadia, this answered the question pretty solidly. While it might make sense for them to do so, GW has laid down the law: it don't happen.

Not a lot of wiggle room to put a SM Chapter in there.

Indeed. The number I just threw out, however, probably explains why they don't recruit from it.

iproxtaco wrote:Equivalent to the Spartan II program? Close, but not quite.

Only thing they're really missing is Mjolnir.

Gene-enhancement therapies have been hinted at since Abnett's introduction of the Kasrkin in "Malleus", and then got hinted at again in Dawn of War's "Winter Assault". It's a bit less solid than I usually like to go on for fluff--but I can't see any reason why we wouldn't see this happening. They may not be wearing something like Mjolnir, but Kasrkin and Stormtrooper Carapace Armor isn't really a joke--especially with the techy bits that have been mentioned as being part of it. NV, pict capture, built-in auspex for the helmets, IFF transponders, etc all hint at it being more than just slabs of armor laid on.

Kanluwen wrote:

iproxtaco wrote:Equivalent to the Spartan II program? Close, but not quite.

Only thing they're really missing is Mjolnir.

Gene-enhancement therapies have been hinted at since Abnett's introduction of the Kasrkin in "Malleus", and then got hinted at again in Dawn of War's "Winter Assault". It's a bit less solid than I usually like to go on for fluff--but I can't see any reason why we wouldn't see this happening. They may not be wearing something like Mjolnir, but Kasrkin and Stormtrooper Carapace Armor isn't really a joke--especially with the techy bits that have been mentioned as being part of it. NV, pict capture, built-in auspex for the helmets, IFF transponders, etc all hint at it being more than just slabs of armor laid on.

I guess we just differ then. SPARTAN II's have extensive bio-engineering, Mjolnir is part of the program. They're stupidly low in number for the scale of their primary conflict, they specialize in hard-hitting spearhead assaults, and have been trained from the age of around 7 due to very particular genetic markers. Sounds more like the Astartes to me. Kasrkin compare better to SPARTAN III's in my opinion. They are mass-produced relatively speaking, have inferior bio-enchantments and armour, and are supposed to be more expendable than SPARTAN II's.

iproxtaco wrote:

Kanluwen wrote:

iproxtaco wrote:Equivalent to the Spartan II program? Close, but not quite.

Only thing they're really missing is Mjolnir.

Gene-enhancement therapies have been hinted at since Abnett's introduction of the Kasrkin in "Malleus", and then got hinted at again in Dawn of War's "Winter Assault". It's a bit less solid than I usually like to go on for fluff--but I can't see any reason why we wouldn't see this happening. They may not be wearing something like Mjolnir, but Kasrkin and Stormtrooper Carapace Armor isn't really a joke--especially with the techy bits that have been mentioned as being part of it. NV, pict capture, built-in auspex for the helmets, IFF transponders, etc all hint at it being more than just slabs of armor laid on.

I guess we just differ then. SPARTAN II's have extensive bio-engineering, Mjolnir is part of the program. They're stupidly low in number for the scale of their primary conflict, they specialize in hard-hitting spearhead assaults, and have been trained from the age of around 7 due to very particular genetic markers. Sounds more like the Astartes to me.

Thing is, the SII program was started before the Covenant were ever encountered. The SII's had already been starting the training process by the time Harvest happened. SII's were supposed to be used as kind of a 'NavSpec' styled team that was going to put down the Insurrectionists and become a bloody nightmare for the rebels. Mjolnir, while part of the program, was also forced to be rushed because of the encounters with the Covenant.

Kasrkin compare better to SPARTAN III's in my opinion. They are mass-produced relatively speaking, have inferior bio-enchantments and armour, and are supposed to be more expendable than SPARTAN II's.

Ehhh. The Kasrkin have 'inferior' armor compared to Astartes...but then again, even most forms of Inquisitorial/Soroitas power armor is supposed to be 'inferior' to Astartes equipment.

You're right on the 'mass produced' part though, but less right on the expendable part. Kasrkin are trained to spearhead Cadian Shock Troop assaults, pretty much being a great big rallying beacon to the Cadians they're fighting alongside.

Kanluwen wrote:

iproxtaco wrote:

Kanluwen wrote:

iproxtaco wrote:Equivalent to the Spartan II program? Close, but not quite.

Only thing they're really missing is Mjolnir.

Gene-enhancement therapies have been hinted at since Abnett's introduction of the Kasrkin in "Malleus", and then got hinted at again in Dawn of War's "Winter Assault". It's a bit less solid than I usually like to go on for fluff--but I can't see any reason why we wouldn't see this happening. They may not be wearing something like Mjolnir, but Kasrkin and Stormtrooper Carapace Armor isn't really a joke--especially with the techy bits that have been mentioned as being part of it. NV, pict capture, built-in auspex for the helmets, IFF transponders, etc all hint at it being more than just slabs of armor laid on.

I guess we just differ then. SPARTAN II's have extensive bio-engineering, Mjolnir is part of the program. They're stupidly low in number for the scale of their primary conflict, they specialize in hard-hitting spearhead assaults, and have been trained from the age of around 7 due to very particular genetic markers. Sounds more like the Astartes to me.

Thing is, the SII program was started before the Covenant were ever encountered. The SII's had already been starting the training process by the time Harvest happened. SII's were supposed to be used as kind of a 'NavSpec' styled team that was going to put down the Insurrectionists and become a bloody nightmare for the rebels. Mjolnir, while part of the program, was also forced to be rushed because of the encounters with the Covenant.

Sure, but they adapted pretty well to the more important conflict. They were low in number due to a sparse number of viable candidates. It's hinted that a second batch of SPARTAN II's were recruited during the war once the population became high enough. That and the entire program was stupidly expensive, those were the constraints on numbers, much like the Astartes.

Kasrkin compare better to SPARTAN III's in my opinion. They are mass-produced relatively speaking, have inferior bio-enchantments and armour, and are supposed to be more expendable than SPARTAN II's.

Ehhh. The Kasrkin have 'inferior' armor compared to Astartes...but then again, even most forms of Inquisitorial/Soroitas power armor is supposed to be 'inferior' to Astartes equipment.

You're right on the 'mass produced' part though, but less right on the expendable part. Kasrkin are trained to spearhead Cadian Shock Troop assaults, pretty much being a great big rallying beacon to the Cadians they're fighting alongside.

And SPARTAN III's have inferior armour to SPARTAN III's. It sacrifices protection, strength, and speed, for stealth.

Everything I said was relative. Relative to the Astartes, the Imperium sees the Kasrkin as expendable assets. There were 486,000 fighting during the 13th Black Crusade, compared to a lot less Astartes. Relative to the SPARTAN II's, the UNSC High Command sees the SPARTAN III's as expendable. 33 original SPARTAN II's compared to three entire SPRTAN III companies of 300 each, 330 for the last.

iproxtaco wrote:

Kanluwen wrote:

iproxtaco wrote:

Kanluwen wrote:

iproxtaco wrote:Equivalent to the Spartan II program? Close, but not quite.

Only thing they're really missing is Mjolnir.

Gene-enhancement therapies have been hinted at since Abnett's introduction of the Kasrkin in "Malleus", and then got hinted at again in Dawn of War's "Winter Assault". It's a bit less solid than I usually like to go on for fluff--but I can't see any reason why we wouldn't see this happening. They may not be wearing something like Mjolnir, but Kasrkin and Stormtrooper Carapace Armor isn't really a joke--especially with the techy bits that have been mentioned as being part of it. NV, pict capture, built-in auspex for the helmets, IFF transponders, etc all hint at it being more than just slabs of armor laid on.

I guess we just differ then. SPARTAN II's have extensive bio-engineering, Mjolnir is part of the program. They're stupidly low in number for the scale of their primary conflict, they specialize in hard-hitting spearhead assaults, and have been trained from the age of around 7 due to very particular genetic markers. Sounds more like the Astartes to me.

Thing is, the SII program was started before the Covenant were ever encountered. The SII's had already been starting the training process by the time Harvest happened. SII's were supposed to be used as kind of a 'NavSpec' styled team that was going to put down the Insurrectionists and become a bloody nightmare for the rebels. Mjolnir, while part of the program, was also forced to be rushed because of the encounters with the Covenant.

Sure, but they adapted pretty well to the more important conflict. They were low in number due to a sparse number of viable candidates. It's hinted that a second batch of SPARTAN II's were recruited during the war once the population became high enough. That and the entire program was stupidly expensive, those were the constraints on numbers, much like the Astartes.

They adapted pretty well to the more important conflict?

You mean where something like they had 90% losses?
The program was indeed absurdly expensive, but that was not because the capabilities for mass production weren't there. It was because most of it had to be built from the ground up, with research ongoing the entire way.

Kasrkin compare better to SPARTAN III's in my opinion. They are mass-produced relatively speaking, have inferior bio-enchantments and armour, and are supposed to be more expendable than SPARTAN II's.

Ehhh. The Kasrkin have 'inferior' armor compared to Astartes...but then again, even most forms of Inquisitorial/Soroitas power armor is supposed to be 'inferior' to Astartes equipment.

You're right on the 'mass produced' part though, but less right on the expendable part. Kasrkin are trained to spearhead Cadian Shock Troop assaults, pretty much being a great big rallying beacon to the Cadians they're fighting alongside.

And SPARTAN III's have inferior armour to SPARTAN III's. It sacrifices protection, strength, and speed, for stealth.

Stealth and the ability to be mass produced without necessitating a lot of fitting and other sundries that the Mjolnir equipment, of which the majority of it had to essentially be 'made for one person', required.

Remember that the SPI wasn't going to be just for Spartan III's. It was going to be issued to ODSTs, NavSpecWarfare Teams, ONI infiltration teams, etc etc. Before the SIII's, the SPI was already underway and it was going to be used en masse when it was needed.

Everything I said was relative. Relative to the Astartes, the Imperium sees the Kasrkin as expendable assets. There were 486,000 fighting during the 13th Black Crusade, compared to a lot less Astartes.

The Imperium sees everyone, even the Astartes, as expendable assets. The only difference is that Astartes lives are considered quite a valuable currency and expected to be expended only when necessary or the pay off is worth the loss.

This has deffinately deviated from topic now lol

I will say that I get what you're driving at.

Yes, the Kasrkin are expendable--but I made the SII comment because of the numbers that you mentioned.

486 Kasrkin Companies(486,000 Kasrkin) compared to the 612 Cadian Shock Troop Regiments(conservative guess of 612,000,000 Shock Troops?) and 16 "Regional Commands"(which I have no real sense of scale for, to be honest but we can guesstimate it being around the Shock Troop scale perhaps?) worth of Cadian Youth Army make for a fairly compelling argument as to the Kasrkin being the "S-II's" of 40k, with the Astartes essentially being the plot armored Spartans who we all know are such huge bad mamba jambas, and Cadian Shock Troops being the "S-III's".

Also, to give a sense of scale as to the deployment for "The Blessed Forces of the God-Emperor of Mankind" for the Eye of Terror...

The entirety of the Space Wolves(12 Great Companies) were there.
The Night Watch(lol?) contributed 11 Companies.
The Dark Angels, Exorcists, Storm Warriors, White Consuls, Iron Hands, Relictors, Angels of Absolution, and Brazen Claws all contributed 10 Companies.
The Marines Exemplar contributed 9 Companies.
The Howling Griffons, Excoriators, and Harbingers all contributed 8 Companies each.
The Angels Sanguine contributed 7 Companies.
The Novamarines and Death Specters contributed 6 Companies each.
The Angels of Vigilance, Iron Snakes, and Doom Eagles contributed 5 Companies each.
The Subjugators provided 3 Companies.
The Ultramarines and Iron Knights provided a Company each, with the notation that it was an "Honor Company" in the case of the Ultramarines. If I remember right, the Honor Company is supposed to be made up of members of the First Company from the Ultramarines and each of their Successor Chapters.

Kanluwen wrote:Now, you've got the makings of a nasty force based on the idea of "experience" because they clearly will have many experienced individuals right?
Wrong. Gangers who were involved in brawls and knifefights have just as little in the way of experience/training as the noblemen's sons who never fired a shot in their life. They have no idea how to operate in combat situations, they have no idea how to behave or utilize fire discipline, or any number of the important things that those Guard veterans already knew how to do.

Space Marines aren't guardsmen, they operate in other ways. The gangers have no IG veteran reflexes to get in the way of the marine training, only the will to kill and maim. And there's the psycho-conditioning and such - I'd guess it's easier to indoctrinate individuals that haven't already been exposed to mass indoctrination like guardsmen surely are.

Civilized people also don't buy the whole "kill this many guys to get one soldier and a few serfs" thing quite as easily as more primitive ones. If you already live on a nice or at least tolerable planet you won't see the whole "fight 24 hours a day" gig as a good thing. But ferals or hive gangers... Take them from hell, put them through hell, then tell them they're the best of the best for surviving it.

SPARTAN IIs - Astartes.
SPARTAN IIIs - Kasrkins.
ODSTs - Cadian Shock Troopers.
Marines - Regular Guard.
If you were to ask me.

Kan knows what he is talking about. Plus, Karskins are easier to make. May not be marine quality, but as Papa Stalin once said "Quantity has a quality all it's own".

Spetulhu wrote:

Kanluwen wrote:Now, you've got the makings of a nasty force based on the idea of "experience" because they clearly will have many experienced individuals right?
Wrong. Gangers who were involved in brawls and knifefights have just as little in the way of experience/training as the noblemen's sons who never fired a shot in their life. They have no idea how to operate in combat situations, they have no idea how to behave or utilize fire discipline, or any number of the important things that those Guard veterans already knew how to do.

Space Marines aren't guardsmen, they operate in other ways. The gangers have no IG veteran reflexes to get in the way of the marine training, only the will to kill and maim. And there's the psycho-conditioning and such - I'd guess it's easier to indoctrinate individuals that haven't already been exposed to mass indoctrination like guardsmen surely are.

This right here suggests you're not actually aware of what the Astartes do.
The Astartes don't do "killing and maiming". The Astartes as a whole are not dumb brutes, let loose in a warzone as shock weapons.
The vast majority of them are quite adept tacticians and insanely thorough planners having thought of most contingencies before they commit a single Battle-Brother to a warzone.
The vast majority of Chapters are quite frankly the perfect example of "surgical attacks". They drop in, sever the command structure, and do this all in such perfectly timed precision that the enemy has no way to respond except by trying to throw ungodly amounts of manpower at countering the issue.

Civilized people also don't buy the whole "kill this many guys to get one soldier and a few serfs" thing quite as easily as more primitive ones. If you already live on a nice or at least tolerable planet you won't see the whole "fight 24 hours a day" gig as a good thing. But ferals or hive gangers... Take them from hell, put them through hell, then tell them they're the best of the best for surviving it.

If you already live on a nice or at least tolerable planet and interact on a day to day basis(like the people of Ultramar do) with a Chapter like the Ultramarines and their Successors, Raven Guard, the Imperial or Crimson Fists, or the Dark Angels and their Successors--then you'll realize it's not "hurr go through hell and do nothin' but kill kill kill". The people of Ultramar think that being selected for initiation is a huge honor and a responsibility.

And Taco, I think you've hit the nail on the head there. I didn't even think to include the ODSTs.

Aw, now I feel all smug.

That's one point I forgot to mention, both Feral Tribesmen and Civilized people see it is an honor to be recruited to their respective Legions. Ultramar particularly has a long standing tradition of it, tracing ancestors who were Astartes.

The civilized worlds as recruiting grounds do seem to be a minority though.

And I don't mean to imply marines (the ones that graduate) are stupid brutes - but making recruits into marines is surely easier if the recruits have less baggage? The body has to be reasonably young to reliably accept all the upgrades, after all. Why don't also go for a mind free of preconceptions about weapons and tactics?

I think cadian marines would be fine to hav and would be easyily moulded into the fluff
Just cos it say they don't recruit from cadia doesn't mean they won't! Might even hav afew in freezer?
And as for sacraficing IG ain't that there job?

U get Deathwatch killteams! Why not stick cadian colours on as the choosen few?
Don't know how long IG live for but Probly not even half that of Marines specialy if the hav to fight lol
But maybe instead of retirement they sign up to the good old Marine TA

Point is anything is possible, fluff may be set in stone sumtimes but there's still gaps to add new stuff
Cadian legend could do same and make sum Merc Marines and come back to cadia to help his skilled cannonfodder mates

Mr. Bloodlustin Monkey, could you please take a bit more time and effort when posting with regards to spelling, grammar and formatting please. Much obliged.

Before I reply to this...'post', I had to go through and correct every error to make it far more understandable.

Bloodlustin Monkey wrote:I think Cadian Marines would be fine to have and would be easily molded into the fluff
Just because it says they don't recruit from Cadia doesn't mean they won't!

Actually, that's exactly what it means.

Might even have a few in freezer?
And as for sacrificing IG, isn't that their job?

You're not understanding the role of the Imperial Guard.

Their lives are relatively valuable, compared to what you seem to be thinking. Commanders who waste Guard lives meaninglessly and/or fail to get the job done in the process tend to be censured or looked down upon by the Guard as a whole.
Commanders do not get glory and honor by wasting troops on objectives not worth the cost in lives.

You get Deathwatch kill-teams! Why not stick Cadian colours on as the chosen few?

Why did you bring up the Deathwatch? They have nothing to do with Cadia, by and large.
Grey Knights are more commonly found operating within the Cadian Gate region than the Deathwatch would be.

The Deathwatch also isn't some kind of magical "haha! victory!" for ridiculous ideas.

I don't know how long IG live for, but probably not even half that of Marines especially if they have to fight.
But maybe instead of retirement they sign up to the good old Marine TA

If you're meaning "Retired Imperial Guardsmen join the Marines" that's just as ridiculous as using the Deathwatch as a way to introduce Cadian Marines.
There's an age limit as to when someone can accept the implants and surgeries of the Astartes. By the time someone is in the Imperial Guard--that age limit has been passed.

Point is anything is possible, fluff may be set in stone sometimes but there's still gaps to add new stuff

Of course there's still gaps to add new stuff.
Except when the fluff is set in stone regarding recruitment and we know that it isn't done.
Just like the concepts of Chaos Grey Knights, Chaos Necrons, Mercenary Space Marines, and Chaos Tau--Cadian Space Marines don't work.

Cadian legend could do the same and make some mercenary Marines and come back to Cadia to help his skilled cannon fodder mates

I have no clue why you started off with "Cadian legend". Are you saying "A Cadian legend", as in there's a Cadian legend who goes off and does it or something?

Anyways. Mercenary Marines is just as bad of an idea. It's rare enough for Astartes to go rogue at this point in the Imperium's history, much less they go out on their own and start working for money(why? WHY? what use do they have for money? Money buys luxuries, what do Astartes consider luxuries?).