jareddm said:

Well, imo the suggestion that SMs need a Progenoid to live is implausible within the canon setting. They were *designed* to be removable - they serve no other function in canon other than gene-seed replication. SMs are extremely tough and keyhole surgery with SM-level technology is not going to bother them.

Imo any remaining Progenoids are removed prior to interment in a Dreadnought. Injuries that warrant Dreadnought armour probably mean that one or more implants have been destroyed. In which case reimplanting Progenoids would result in incomplete gene-seed replication.

What you suggest is a variant setting. You can come up with whatever you like.

There's an easy explanation why a decades-old marine would still have his progenoids... Since removing them cleanly most likely involves a lengthy and delicate operation (going through the Black Carapace as well as a fused ribcage) they probably need a lot of time to do it, bot the prepping, operating, healing. And since a lot of marines just go from battle to battle to battle on board a small cruiser, they might simply not have the opportunity to be in a sickbed for weeks on end... or the Apothecary with the required skills and /or equipment might simply not be available.

There is no reason to believe Progeniod glands are large or have a big blood supply. The key-hole surgery to remove them would be quick and require minimal preparation and recovery. Going through the Black Carapace and Ribcage isn't going to phase a SM surgery table which makes a Narthecium look basic.

Retaining these glands past maturity would be a matter of Chapter tradition. No medicine or practical reasoning is required.

The fluff describes them as being not tiny, but more the size of a walnut or peach. (In the older fluff anyways) So in my opinion, invasive surgery would be required. But anyways, there could be any number of reasons why an 'older' space marine would still have them. In game terms, perhaps a random roll when he dies too see if any given NPC marine still has geneseed?

Real World doctors remove kidneys with keyhole surgery. And that's with the medical equivalent of flint knives compared with Space Marine surgical techniques. An explaination based on surgical concerns just don't strike me as credible within the setting.

As I said, if you want SMs to generally carry Progenoids, you can say it's widespread tradition amongst Chapters - gene-seed is generally harvested from fallen Brothers. Removing them from a living Brother is simply not done. This is completely in-line with the fluff on collecting Progenoids from the battlefield.

Going back to fluff sources, the book "Legends of the Space Marines", or Heroes, the one with the Scythes of the Emperor story, I thought mentioned that the sergeant in the story mentioned that all the veterans had given up their progenoids for the creation of new initiates, yet he still wondered how they were getting the number of new recruits they were.

Still demonstrates in fluff that progenoid removal is not a life ending procedure and the marines can still function like marines. For some it might even put their minds at ease on especially dangerous missions because they know that the mission can come first and that no one will have to risk reaching them to retrieve the glands should they fall.

E

if i well remember....

there are two progenoid gland....one was removed when mature.....

and the second, if possible, when a space marine die....