I'm not sure if this belongs in the Gamemaster section or here, so I decided to try posting it here.

What do you think of a Grey Knight that is an Untouchable? Although a Grey Knight with no Psychic Powers would be odd, he would have the benefit of being immune to any Psychic Powers or Warp effects, making him really powerful against Daemons. Is this idea too outrageous or too outside the scope of the fluff/storylines? I was thinking of having such a character as a recurring NPC in my Dark Heresy campaign when my group eventually gets to the point where they will be occasionally dealing with Grey Knights, I would like your thoughts and opinions before deciding. If such a thing were possible, how would Nemesis Force Weapons (and other Grey Knight specific gear) function in the hands of a Untouchable Grey Knight?

My understanding of the fluff (I haven't actually read the DH rules for GKs) is that such a character couldn't benefit from any of the Grey Knight tech which almost invariably are at least a force weapon, or are psykically active in some other way. An untouchable space marine of a different chapter could work. Such a person would likely be virtually unique even amongst the teeming mass of humanity in the galaxy to be both untouchable and have the requisite 'stuff' to become a SM. Such a SM could very well find himself called to the Deathwatch or somehow seconded to the Ordo Malleus as epically useful vs demons.

So in a word I would say no to a GK for fluff reasons, but you could use a similar character. On the other hand if you are set on using GKs in your campaign they might well use untouchables as part of Inquisitorial cadres fighting alongside GKs, and if such a person were prominent they could well be a conduit to your PCs getting a closer relationship with them.

The problem with the Grey-knight untouchable is that Grey-knights tend to work together: one of the prerequisites to joining the group is to have at least some psychic potential.

An untouchable would be counter productive, as any meaningful power level of one would disrupt his team-mates just as much as any daemon, perhaps even more so, and any "weaker" one would have any protection gained by his status superfluous as holy items and wards on armor actually exist and are a valid way to protect Vs Warp attacks.

I do like the idea of an Untouchable Space Marine as a particularly Unique Individual- or ultimately, perhaps an Inquisition secret project, but such a thing should be a plot unto itself

An Untouchable Space Marine would be both incredibly rare and incredibly powerful. Some Black Library books include Untouchables, and even a weedy human Untouchable is horrifically effective against psykers and Daemons. Such a Space Marine would almost certainly find himself on very special assignments (like service with the Deathwatch or an Inquisitor) but wouldn't work well as a Grey Knight for the aforementioned reasons. He might belong to another Marine chapter that particularly detests psykers (Black Templars come to mind, though other origin chapters are certainly possible). All in all, sounds like a very interesting idea for an NPC.

If this Marine becomes a recurring character in your campaign, be careful to keep the story's focus on the PCs. A powerful and unique NPC can be a very memorable character, but the players will feel marginalized if he gets too much "screen time." Dark Heresy is a game about the Acolytes, after all

An Untouchable Space Marine would be both incredibly rare and incredibly powerful. Some Black Library books include Untouchables, and even a weedy human Untouchable is horrifically effective against psykers and Daemons. Such a Space Marine would almost certainly find himself on very special assignments (like service with the Deathwatch or an Inquisitor) but wouldn't work well as a Grey Knight for the aforementioned reasons. He might belong to another Marine chapter that particularly detests psykers (Black Templars come to mind, though other origin chapters are certainly possible). All in all, sounds like a very interesting idea for an NPC.

If this Marine becomes a recurring character in your campaign, be careful to keep the story's focus on the PCs. A powerful and unique NPC can be a very memorable character, but the players will feel marginalized if he gets too much "screen time." Dark Heresy is a game about the Acolytes, after all

Thanks for the suggestions. The way I'm running my game, whenever the Acolytes are in a situation where they have to flee and their Inquisitor has to summon the Grey Knights, the characters themselves will be playing the Grey Knights. Basically, every so often, I will have a couple game sessions where the players play their Grey Knight characters to deal with the situation for which the Inquisitor called on them. After the Grey Knights complete their mission and report back to their ship, the group will go back to playing their Acolyte characters. So there will never be any over-powered NPC's outshining the characters. And the group will get to have fun with the occasional interlude playing super-powered characters.

Thanks for the comments, everyone. Based on your suggestions, I decided there won't be any Untouchable Grey Knights in my game world. And as I said to "Covered in Weasels," the only time the Grey Knights will make any significant appearance in my campaign is when the players themselves are playing Grey Knight characters during interludes where the Grey Knights have to be called in to deal with something that the Acolytes can't handle. This will also be my excuse for my group to occasionally have fun for a couple game sessions playing super-powered characters. It will also prevent super-powered NPC's overshadowing my players when they are playing their Acolyte characters.

Incidentally, I thought it interesting that a couple of you mentioned a normal Space Marine being an untouchable. I am taking part in a campaign (involving Deathwatch and Ascension-level Dark Haresy characters) run by a friend where my character is an Untouchable Space Marine. Because of his unique status, he has been permanently seconded to the Deathwatch.

Ultimately, it's highly unlikely to have an untouchable make space marine unless it's a chapter which makes a standard practice of it (which I'm sure the inquisition in it's infinite deviousness has tried at least once!) or a bunch of witch-burners like the Black Templars.

The reason is this: In every 'normal' chapter, part of the sifting process to determine suitable candidates for induction is psychological examination of every level of the aspirants' concious and subconcious psyche. An untouchable cannot be so examined. Yes, they are more resiliant to the touch of chaos but there are any number of non-daemonic things the librarian would be searching for, from phobias to cowardice to psychosis.

Can't be examined - can't be certified pure - unsuitable - dump them.

There are exceptions to every rule, but it's going to be massively rare (even by the standards of untouchables) as a result.

Don't. A Grey Knight has enough going for him that you don't need to muddle the waters with the untouchable stuff.

All grey knights are psykers, untouchables are incapable of being psykers as far as I know. So no.

It really makes no sense to have a blank Grey Knight, as they are solely selected from Sanctioning candidates on Terra, and blanks simply aren't sanctioned.

Even if, due to some administrative hiccup, an untouchable was sent along other candidates to Titan, he would have been found out and executed (so as to ensure the secrecy). Grey Knights' combat doctrine is fully reliant on all of them being psykers, so they have absolutely zero need of a blank in their midst.

So no, it's literally impossible for such a character to exist.

In the novel The Emperor's Gift, the funerary tradition's of a fallen grey knight were described, and they showed one grey knight that was a psychic blank, referred to as the Ferryman. He was the one who the body was handed over to when they are to be interred in the Dead Fields. They apparently have at least one grey knight who is a untouchable (potentially a small sub-order of them?) that tends to the fallen. Just thought I'd throw that in here.

Didn't know we had high-level necromancers on this thread, what level spell slot does it take to perform this sort of ritual?

Jokes aside, the BL books are a place you should only venture to for actual fluff at your own risk. They are notorious for being poorly researched at the best of times, and seeing as how every Codex and official source concerning the Grey Knights is adamant about their all being psykers and going by the fact that all of their weapons and gear are psychically active (Nemesis Force weapons and the Aegis system in the power armor being the prime examples) I severely doubt the existence of an Untouchable Grey Knight.