Ok, I've run three sessions now, and I'm finding that I'm running into a problem.
When I first started researching Dark Heresy, I read quite a bit from people suggesting that starting Acolytes were just far too squishy. I tried to keep this in mind, and created combat encounters that I thought were challenging but not completely overwhelming. In each combat I generally used 1.5 opponents per Acolyte, so the PCs were typically outnumbered. Using the stats provided in the book, I've thrown them up against Mutants and Abominations, Cult Intiates and Fanatics. It doesn't matter; the PCs seem to be untouchable. We've had five combat encounters so far, and the PCs have yet to take any damage (physically, anyway; they have managed to rack up some Insanity and Corruption points).
It seems to me that the NPCs provided in the Dark Heresy corebook are just not very effective. I'll admit that my PCs all rolled uncommonly well on their BS attribute, but the NPCs are just getting torn apart. I've only managed to score a single hit with the NPCs' lousy WS/BS, and it did so little damage that the PC effortlessly soaked it. Meanwhile, the PCs are mowing down heretics like it's going out of style (it doesn't help that the psyker tends to soften the NPCs up with his Fearful Aura before calling in the rest of the gang to mop up).
Is there something that I'm missing here? Is there something that I should be doing to put the tiniest bit of fear into my players? I'm not looking to completely overwhelm the group, so dropping a Lord of Change into the game isn't the answer that I'm looking for; I just want to know how to make the NPCs that I'm using present the tiniest bit of a threat. The PCs have just reached Rank 3, so what makes for an appropriate challenge, and how can I make the most of it?
). OR you pit the PC's against particularly insidious big baddies that will try to lure the PC's into fighting on it's own terms (like a tyranid Lictor, stalking some seriously narrow alleyways in a dark part of town, and it will try to break up the group of PC's into smaller fractions and try to take them out one by one, instead of going up against the entire group at once etc.)
And ... technically, in DH, caution should be the norm, rather than the exception. This setting should be both lethal and horrific, IMHO.