The Grey Knights are bar the Custodes the greatest warriors the imperium has. Each one is utterly fearless, dedicated and trained to fight and stand against the greatest enemy Humanity/Reality has. There is no such thing as a lowly newbie Grey Knight.
The fact that not all of them manifest psy power is not because they have none it’s a matter of safety and training. They channel their psychic might though items such as weapons or as a unit, to protect against corruption, possession, ironically much like the Elder do.
Only the most experienced Grey Knights are deemed pure and strong willed enough to directly project psychic power, you must remember the enemy they fight.

They are Humanities ultimate champions.

Sadly Grey Knights would not fit in a Dark Heresy game as a playable character maybe a Deathwatch game with it missions and objective's providing a focus for these dedicated champions of Humanity, but unless the entire party were Grey Knights a Grey Knight would overwhelm even ascended characters to say nothing of the moral compromises that Acolytes must make. A Soroitas is a hard core Zealot but that’s based on faith. A Gray Knight's Zeal is based on knowledge of the truth concerning their enemy.

Purity is life or death to them literally.

Immortal said:

There is no such thing as a lowly Grey Knight. There is such a thing as newbie Grey Knight and they are the ones that wear power armor.

Grey Knight might be the mightiest when it comes to martial skills, but that doesn't necessarily mean they're the best or how they compare on the use of tactics. They specialize against daemonic entities, against more mundane units they may run into problems. It only takes one vortex grenade to ruin anyones day. I'm not saying you're wrong just that the scope you're applying to them may be broader than it should be.

Kasatka said:

I really hope that the Grey Knights aren't playable. I'm hoping for another Combat orientated RPG ( like Deathwatch ) where a Squad of Grey Knights purges demons. That would be AWESOME!

I'd say the chances of an entire new RPG line just for Grey Knights is slim. At tops, I'd expect one Deathwatch supplement covering how to do them, but I'm doubtful of even that.

I can't see Greyknights being playable within Dark Heresy as they would throw the balance off, also not being in Deathwatch as it is a distinctly Ordo Xenos game. And obviously not in Rogue Trader either.

Untill FFG come out with the second edition of 40k RPG and adopt a more sensible approach of 1 universal core book with everything else being a supplement for it, with source books for each supplement (See the World of Darkness Core -> Vampire core -> Bloodlines books as an example).

I think if Grey Knights were ever done it would be a self contained expansion to Dark Heresy that would bring only some elements of Deathwatch in.

aka_mythos said:

It shouldn't bring any elements of Deathwatch into. Greyknights are a dedicated chapter with their own gene seed, unique equipment, training and forbidden lores.

Deathwatch is a temporary assignment drawing from all other chapters (bar Deatchwatch afaik), with only some unique equipment, training and lores.

The only thing that could really be ported over would be the creation rules, but then youd all have to pick the same chapter so it'd become homogonized, at which point you might as well just present it as a template instead of explaining the creation rules then not having any options. You could still have background packages to be bought with XP though.

Grey Knights would fit in both on a sheer technicallity....... DH uses all the various strands of the inquisiton and thus would allow GK to appears as he could easily tip the balance in the favour of the party on a lost deamon infested world or he could become thier worst nightmare if they stray too far from the rightous path either way good gaming can be had by all..... DW they fit but in the loosest sense (as in 1 sentance from the DW fluff history) " the DW take the best marines from EVERY chapter in the imperium of man in their fight against the xenos" and yes i know its has never been said anywhere that the DW have seconded a GK but in theory its possible

lord inquisitor revan darksoul said:

No it's not... the chambers militant of the three Ordos are entirely seperate entities, the only people who can boss them about are inquisitors, and even then usually only of the respective Ordos. There's no way an Ordos Xenos Deatchwatch unit would demand an Ordos Malleus Greyknight be seconded to them and not get a new a-hole ripped.

Kasatka said:

And only then if the local Order Militant leader thinks it reasonable and suitable for their subordinates to help that Inquisitor. There have been cases where Deathwatch troops have said "sorry, we're busy" and not helped out.

there have also been cases of inquisitor lords in the fluff belonging to more than 1 ordo so its stands to reason that its possible but have never been done in story or fluff. as previously stated the GK are their own chapter and are the effective millitant arm of the mallius but the death watch take marines from every chapter in the imperium and that is canon so its possible even if its has never been done

Where does that fluff come from? I've never heard the multiple ordo Inquistor thing before.

Kasatka said:

The Exorcist chapter would be an interesting variation to bring to any book about the Ordo Malleus, Daemon Hunters, and Grey Knights. They were created by the Grey Knights to supplement their capabilities against daemons. The Grey Knights will ritually allow Exorcist marines to be possessed, casting the Daemon out once a battle is concluded. Because of the repeated possession the Exorcist marines have a larger degree of control and are also less prone to unwanted daemonic possession.

aka_mythos said:

it was origionally metioned in the death watch books i belive of the top of my head and briefly in some of the codex fluff for ordo hereticus in the hstory of the inquisiton but i will double check and give you a definitive answer when i re read that particular bit.. (or ill cheat and ask at head office)

I'm all for BL writing their novels, but at the same times it introduces greater inconsistency in the setting. Outside of what you're citing, the Ordos rarely cooperate and rarely trust each other. The different Ordos have been stated as having fought each other when they're both pursuing similar yet conflicting missions. Inquisition trusts no one, not even itself. The amount of "trust" an ordo would have to intiate an outsiders would be ridiculous, the Emperor himself would half to hand down the order himself. Within an Ordo an acolyte is selected almost like an apprentice by an Inquisitor Lord and then be accepted by a number of the Inquisitors peers... to then turn around and do that with a second Ordo seems like it defies a lot of the nature of the Inquisitions.

Now on the other side of that coin I could always imagine a lesser Ordo accepting someone from a more dominant Ordo if they believed it would bring them additional resources.

In my opinion, Deathwatch is the perfect thing to work with.

A Squad of Grey Knights fighting against hordes of Demons, CSM or posessed Humans. DH wouldn't really fit, in my opinion. GK are too powerful to be included in a normal "Warband". Background would be fitting, but the squad based thing of Deathwatch would be perfect regarding the game mechanics.

There's not going to anything stopping anyone playing any version of SM's when Deathwatch comes out and there's already a fair amount of the equipment in DH, but I can't see FFG supporting it themselves due to afformentioned limitations.

Another consideration is that Grey Knights are not generally known about - even the other Space Marines (even the ones seconded to Deathwatch) don't know of their existance. They are a super secret organization.

From Codex: Daemonhunters:

"The most secret of Chapters in the Imperium"

"there are many recorded instances where subsequent Imperial forces have arrived tio find the foe defeated with no clue as to how"

"Some of the greates heros of the Imperium lie buried beneath throck of Titan but, like their Chapter's very existance, no one can ever know of them."

Now you can draw your own conclusions from this, but I always got the feeling they wern't even known about by the other branches of the Inquisition - That each branch was successively more reclussive and secretive, and kept things from the lower orders Herticus ==> Xenos ==> Malleus.

Nor could you use normal Space Marine generation rules for making Grey Knights - They have better enhancements, more training, they are all potent psykers, they have special equipment (Aegis Armour, Nemisis Force Weapons, Psycannons, Psycannon bolts for their bolters).

Some of their original fluff, they would wipe out Imperial Guard regiments and space marine companies just to keep the secret of the existance of daemons a secret. That shows how "secretive" they are. With more recent fluff GW's lightend up on that aspect to them; this can be written off as "the cats out of the bag" and they aren't as intent on keeping daemons a secret.

Personally, given at least the fact there is some compatibility, I expect the further supplements to start making more mention of other parts of the line. Just as Ascension and Rogue Trader make some notation of how to cross over.

So the Grey Knights? They'll probably be statted out to allow Ascension level Inquisition groups to call on them in case of extreme demonic threat. Just as there might end up being something similar for Ordo Xenos to call on a Deathwatch team. I wouldn't be shocked if it is then followed by a section on how to make them if you have Deathwatch.