Hi there reasonably new GM here,

I've been leading my party through a few premade adventures and I would like the next adventure to branch off and be my own, however I was hoping to get a bit of help/advice on creating the new setting.

My thoughts so far are as such, recently a large imperial cruiser has gone radio silent, the acolytes are tasked with travelling to the ship, establishing a base of operations and finding out what has happened.

The party will arrive at the ship and initially it will be deserted/ lots of dead bodies and they will explore and set up camp (some ideas of possible tasks/rooms would be good here)

At some point they will discover a small party of necrons and this is obviously the reason for the dead bodies and the ships lack of communication. (not sure what to make the trigger)

I’m just not sure how to finish this off, or even if necrons are the best choice, they are very tough and at this point in the timeline there aren’t very many of them (though that does give a fear factor in that none of them would know what they were facing)

First, they`ll need to actually get into the ship. How will they be transported - by Guncutter and they have to find a bulkhead? By a dedicated boarding-ship, which they just need to attach to the ship and wait for the ship to cut open the hulk?

Next thing would be finding a place with atmosphere and, ideally, gravity, with the Grav-plates being potentially unpowered, so they`ll have to restore power etc etc.

Then they`d probably work their way through to the cogitator-core or the bridge, a long journey through corridors, crew-quarters, maybe the occasional sub-command-room, possibly ammunition storage, hydroponics, freshwater-tanks, life/sustainers, perhaps void shield generators, etc etc.

If you use Necrons (I`d probably advise against that, since they ARE tough... really tough, even for Rogue Trader characters with all that fancy-shmancy gear) you could use a single Canoptek-Wraith stalking the corridors, with the players occasionally taking a glimpse at it at the edge of their perception, or blurred security-footage hinting at the stalker. They would then have to somehow hunt it down (It relies mostly on Hit-and-run-attacks) and ultimately get some vox online again so they can report to their superiors.

Other alternatives would be Genestealers (again, rather nasty) or Slaught (in which case the brains from the corpses would`ve been removed), but I could also imagine a lictor (how the hell did that thing get here? And what does it mean for the calixis?) or perhaps a daemonic entity (maybe the crew wasn`t so loyal after all...).

Anyway, my two thrones for now.

One thing that you have to think about is that you are removing your players from EVERYTHING if you put them on this space station. Wounds are suddenly a bazillion times worse, the death of a party member can mean that the whole game is over, each and every bullet, bandage, ration are now so many times more important. That is if you play with a deserted and spooky ship, because why else would you use a ship like this?

Do think a lot, and get your players think a lot before they say yes to this mission and leaves their planet, it could very much end like an one way trip after all

Have you seen Event Horizon?

Have you seen Event Horizon?

This was my first thought too. Daemons are also the most readily customisable threat. They can be as weak or strong, few or numerous as you wish.

It also gives you the opportunity to present the players with an undead Captain who appears to be fused into the bridge, and mumbles dire warnings at the party in High Gothic, as it was spoken during Goge Vandire's reign.

My second thought was Alien 3, particularly the scene where the convicts are lighting up a long, dark tunnel and something keeps blowing out the light just outside their field of vision... Before it starts to ****** the convicts one by one. It's basically what the Lictor Darkforce mentioned was designed to do.

My third thought was I'm not super fond of Necrons & Tau, so if I were you I'd go with pretty much anything else. But tastes differ & stuff.

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I don't mean to disagree with Doomande, but generally speaking, Warp-capable ships in 40K are pretty much space-based cities. There's no reason the ship shouldn't have hospital facilities, chymist & engineering workshops, murder servitors the players can take charge of, library facilities to help them with research, and whatever else they might need.

That said, you should try to make every location feel like it's ship-born and not planet-side.

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As for how to end the scenario, there's at least a few obvious solutions. The ship itself is an incredibly valuable thing. Purifying and salvaging it is a perfectly reasonable excuse to send in a few hundred Astra Militarum (or whatever the IG is called, I suck at names) under the command of the Acolyte Cell.

If that's not good enough for you, the ship is presumably going somewhere. For example, it could be going to Footfall.

Of course Footfall (and similarly critical trade hubs) typically do have the firepower to turn a single ship into slag, even if it's a very big ship. But the slagged remains of a ship impacting a space base is still going to be incredibly bad, probably kill tens of thousands, and almost definitely disrupt trade for months - trade that several colonies undoubtedly rely on to maintain their existence.