I'm pretty new to the system and I've recently started a character in Black Crusade. Myself and a few others in the group are very into making elaborate plots which prove to be the downfall of planets. Seeding ruin through deception and planning just feels so much more rewarding than storming in with a legion of Bloodthirsters.

For the first time in the system I'm making a character centered around ultra stealth. I'm using the character to seed evidence/frame/blackmail/etc.

I've invested in the synskin/Camoleoline combo, gotten access to unnatural agility/stealth, as well as a few stummers to boot. I feel like I have the gear and built the character to succeed.

Am I missing anything? I've gotten a few comments from my GM about psykers having the ability to see people's souls, with other psykers/daemons/dark eldar standing out in particular. I've read up on a power in Dark Heresy called Sense Presence which seems to accomplish this to some degree. Is there any way to combat this in the system? Any pacts that seem feasible? Any ritual to hide my soul completely, or in the very least replace it's appearance with something at least incongruent with my body like a fly or small insect?

You could ask you GM about the possibility about seeing if you can be a 'blank', with all the role playing problems that causes. You could also try and obtain a Null Blocker (Ascension), the Inquisition uses it to protect from psykers and it might block the use of such powers on you. It is only a 50% shield though. A special ritual that lets you overlay someone else's soul onto your own for camoflage might be possible, but it would require GM permission to design. There may be something else in the Black Crusade books, but I don't know offhand.

Only thing that comes to mind would be Blood God's Contempt (other than Collar of Khorne, that is) to have a chance to resist any psychic powers targeted at you, if that's the issue at hand.

or get an untoachable as a companion or as a player

Eldar soulstones achieve this to an extent - certainly, it's part of the reason the Eldar use them. However, getting hold of them does run the risk of encountering some very angry Eldar...

I asked this myself fairly recently, looking for ways to hide my presence entirely from all known sources where possible. Thing about Untouchables or Blanks, I don't know how you lot see them but I imagine Psykers, when things scour the warp, the regular people are like shadowy images, daemons and psychic things glow but blanks and the like stick out like a sore thumb as an obvious gap. You dont see the blank but you see the gap or aura in the warp that they leave by not registering in it. Dunno if it was ever fully mentioned though how it appears to them.

true it could be like that too

From what I have read in the Ciaphas Cain novels and from what I remember in the talent in Dark Heresy, being a blank makes it so you dont register in the warp at all. Your presence in the warp is not as a shadow or a void.

The example I can come up with is if the warp is a still water men are like some one with thier feet in the water, a psyker is waist deep and a blank isnt in the water at all. Men cause small ripples, psykers small waves, but a black can not affect the pool and thus are not effected by it.

From what I have read in the Ciaphas Cain novels and from what I remember in the talent in Dark Heresy, being a blank makes it so you dont register in the warp at all. Your presence in the warp is not as a shadow or a void.

The example I can come up with is if the warp is a still water men are like some one with thier feet in the water, a psyker is waist deep and a blank isnt in the water at all. Men cause small ripples, psykers small waves, but a black can not affect the pool and thus are not effected by it.

There are, however, varying degrees of Null. Those trained by the Templum Culexus, with their powers augmented by the technology implanted into them, are described by their prey as howling abyssal voids, an absence within the darkness too horrible to behold. It may be that only the most perceptive can truly perceive them - it would be akin to spotting a Black Hole with the naked eye against the seemingly-empty darkness of space.

This all aside, it's reckoned that while most baseline humans can't consciously perceive the Warp, they unconciously do so all the time. This accounts in part for a sense of "being able to read people" - those who are more sensitive to the Warp can glean more from passive observation of the souls around them. Humans instinctively distrust Nulls because they can't be perceived psychicly, and regard the high-magnitude ones like Culexus Assassins with a kind of horrified disbelief (as their minds fail to rationalise and acknowledge the discrepancy between their material senses and their immaterial sense). Psykers, whose psyniscience is a developed sense, tend to regard a Culexus with abject terror, because they don't have the luxury of subconscious denial.

So basically it's open for debate...

Yep...

Always imagined Nulls to actually be detectable via Psyniscience, though not with other means of scrying. But thats also due to me imagining them to be more like "voids" in the background static of the warp. Fits more with how they mechanically affect psychic powers and such as well. Just my opinion though.

With regards to getting past Psyniscience and Divinations, sorcery is the answer. Granted there is nothing in rulebooks for doing so... But where there are ways, there are ways to counter those ways. Say an Amulet of Non-detection. The good thing about RPGs vs competitive games is that if you want something just invent it, with GM permission and cooperation of course.

//Oh yeh, not sure of Nulls/Blanks can be corrupted by the Ruinous Powers. They are basically warp-immune after all.