With Haloween coming up, I am thinking of running a horror mini-game of only war.
I'm looking to simplify the rules for quicker gameplay and maybe introduce aspects of Black Crusade as players go mad and get mutations. An aspect I am keen on introducing is secretly making one of the players a 'traitor' or some role that'll aim to hinder the squad. This'll create an atmosphere that is uncomfortable to the players as they will not know who to trust. Furthermore, maybe giving them secret objectives as to make everyone seem more suspicious (althought I am unsure how to do this).

So far, I have the idea of they are on patrol and come across an abandonned trench/bunker.
They'll be ordered to searching it via that Vox and once entering the position, will lose comms and get lost in the vast complex twists and turns. Maybe later hearing voices from it and other nasty boooby traps and bad stuff happening.

Can people leave suggestions on how I can simplify the rules, what ecounters they could possibly face and generally how to bring the horror element rather then bland fire fights/roleplay that can sometimes happen.

Thanks guys, happy hunting!

Creating a horror inviroment is tough.

But a nice example would be Aliens (the movie).
Have them walk through endless corridores, have them make Perception test at random. Ask by how much they make it or fail and just write it down. This will make the players think something is up. If they truly Ace a test just have them hear something, a distant scream for example.

Now I do no recommend Genestealers as enemies but perhaps you could upgrade/alter some Hormugaunts.
Have them escort some civilians, important enough that they have to protect them.

At some point just have a npc drop dead, perhaps he was poisoned or infected with something. Have communications falter.
Make sure they have less ammo then expected. Maybe the civilians need to arm themselves so they have to give up their sidearms.

Put a timer on them, maybe command will gas the city block/area after some amount of time. To motivate the players you could use a timer of sort. Two d10 could easily be used as an XX hour count down.

Of course evac point alfa should be comprimised and with communication down or bad finding point beta should proof difficult.

S.

It's likely to be done online over skype and Roll 20, which is an advantage because I can easily message each person individually prehaps adding a sence of suspicion as I may leave clues hinting that their other team-mates may be involved in what is happening around them. I like the idea of having civilians cause their actions could draw the players away from the real threat or make themselves more suspicious of one another.

I've got ideas of hallucinogenic effects, including but not limited to the table from the grenade, prehaps finding other guardsmen who have suspicious deaths and survivors who may at first seem normal then turn out to be homocidal psycopaths. Maybe make it possible to make one of the players secretly turn on their team as with Gmod's Trouble in Terrorist Towwn? Or prehaps force the players into desperation like leaving one respirator with some of them trapped in a room filling with gas? Maybe even start some players with some negative traits like paranoia or certain drug addicitions so that their acts make them suspicious?

Your idea sounds a bit like this movie

Don't use Genestealers or something the players will recognize.

Send them into an haunted insane asylum. Or haunted funhouse. Or haunted ruined noble manse. Or something of that nature.

They're fighting rebels on a hiveworld. Ruins everywhere. Their squad follows the enemy into the the aforementioned insane asylum/funhouse/whatever. Maybe one of the patients was a latent psyker of great power, mind snapped by the war. Now the place has become a thing from hell.

Do lots of non-combat fear tests leading to rapid insanity point acquisition. Leading to lots of mental trauma. That should do it.

Hell, have them be hunted by a classic slasher. Jason Vorhees.

Drop the military theme halfway into it. They're not dealijng with something that firearms can take out. They're dealing with unstoppable,supernatural evil.

hmm. Chaos cannibal cult? Maybe not even Chaos. Just cannibals.

Or make it all a dream, when the last PC dies.. have him wake up….

Only make them wonder was real or not.

Challenge Magazine had a module like this for Twilight2000

Or make it all a dream, when the last PC dies.. have him wake up….

Only make them wonder was real or not.

Challenge Magazine had a module like this for Twilight2000

"You are all standing in line before the Commissar. In your underwear."

I used dark eldar and they worked PERFECTLY. Seeing shadowy figures move around, people dissapearing in the darkness. Stuff like that works great. A mandrake works the best, however it's immune to most attacks if it dodges so that's not good unless you have power weapons and psychers, but even the normal DE's work great.

Might not be as good up against rookie guardsmen though.

Be liberal with the insanity points.