I've been thinking of a good way to introduce a couple of new characters into the campaign (and lose a couple of others whose players have left) which doesn't seem too stilted. The players screwed up their last mission rather spectacularly (Ambulon has since been limping noticeably), and, having been debriefed, rebuilt and let out of ICU, have been assigned a new one with a minder to report on them. They have already been sent on this mission and I have two new people wanting to join the campaign.

Rather than have them take over the 'spare' characters, or have to hang around until it makes sense to introduce more acolytes (either as official reinforcements or random people they have just met and hired), I've decided to essentially just go 'screw continuity'.

The party will, in the course of its' investigation, stumble across something deeply weird and heretekal (for reference, I've given it the working codename of 'the Alternity Device'). Being player characters, the odds are that they'll ****** it from the strangely affluent (and deeply miserable) lowlife owning it (either with or without killing him doesn't matter). While my players are rather genre-savvy and aware of the CoC advice (stay in the middle of the group, keep your eyes closed, don't read anything, don't touch anything, and if you hear a noise point your shotgun at it and pull the trigger), I'm fairly certain that one of them will fiddle about with it before handing it over to the Inquisition/AM. If they don't, then their minder, or possibly the former owner/one of his friends will. There will be a flash of bright black light, and when they can see again the Alternity Device, and all traces of the bad guys and any recent combat will be gone. If they thought of taking one of the 'spare characters' along as muscle, that character will also be gone.

When they get back to their base of operations, the new PCs will be there, with full knowledge of the investigation up until the trip the others had just made. The Minder, Interrogator ibn Stein, will treat it as if nothing is out of the ordinary, and will be confused by the suggestion that something is wrong. Every NPC (and the two new PCs) will be convinced (and may even have evidence to the effect) that the replacement characters have been with the group from the start. The Minder will have been assigned to them to evaluate their potential, rather than sit as judge and executioner, and the events of their recent failure will have acted out differently- they will have succeeded handily, with little collateral damage and injury. The bionic rebuild the psyker received will apparently have been for something completely different.

Essentially, I want to see how the existing party reacts to this, see if they figure out what happened, and whether or not they will try and find a way to change it back.

As for the Alternity Device- I see it as being either a form of Halo device (unlikely), or some form of warp technology which shifts its' target into a timestream/parallel universe which is the 'best' outcome/sequence of events that could plausibly lead up to their current physical state. However, I'm not particularly sure about that part.

Thoughts and comments, anyone? I'd especially appreciate better ideas for the 'alternity', and I'm not 100% wedded to it being an item- a daemon/psyker/warp rift/alien could work too.

Basically, is this a good idea? Thanks in advance.

Easy option is that thier Inquisitor now doubting thier compitance has sent a second team to Inversigate without the knowledge of the first team. The second team may have come across something that they cant handle and 2 of the members die (random NPC's). The new PC's get turned around and then find the first group by accident, make sure the second group have the right papers and know about the first then run the scenario from there with both groups. If you want you could take the 2 new members and run thier intro before the main session so that they know whats going on.

Kaihlik

sounds fun. and i find it a good way of introducing a couple of new characters.

sounds like a splendid idea, you could build entire campaigns off that little device

and sounds very tzeentch to me

its a good way to introduce new pc's and a good way to change mission/objectives,

now that i think about it im stealing that device as a plot hook, hope you don't mind to much

Thanks for the comments.

It has been posted on 'teh intarwebz', therefore it is fair game. Just please don't spill it on the main board here, or on RPOL for a fortnight or so, give me a chance to hit my players with it.

I have to admit, I'm still trying to figure out how I want the Alternity Device to work- I'm currently leaning towards a technological 'wish granter', which can be manipulated to provide pretty much any effect the user can think of, assuming [he] knows how to use the controls properly.
Another option is something akin to a Banks-ian 'Lazy Gun', which are (presumably) self-aware weapons with a sense of humour- they'll invent some method of killing their programmed target and it will 'spontaneously' occur- impaled on a suddenly materialised swordfish, transformed into a pile of banknotes which then blow away, drowned by all the air in their lungs turning to butterscotch custard, or (as in this case) whisked off to an alternate timeline. This option, I'm less fond of, although I know that at some point I simply have to include a Lazy Gun, possibly as a jokaero custom jobbie.

If anyone has any good ideas for the Alternity Device (up to and including a better name, if you can think of one), I'd welcome them.

Sounds like a great way of introducing some new characters. I would be wary about overextending its use though as super powerful items can begin to dominate the game and even the setting.

I once played a WFRP adventure where I introduced a bag which had infinite room inside it more as a curisoity really. It ended up causing all sorts of problems.

I would have all sorts of strange and at first innocuous differences and wierdness that gradually grow in strangness and possibly horror.

As for the origin I think some kind of either Pre-Fall Eldar device could be interesting or Dark Age of Technology.

Or it could all be a scam their Inquisitor is hitting them with 1) to see if they're bright enought to figure it out, and 2) as punishment for screwing up.

I absolutely love this idea. And especially the comment Kaihlik had about another team loosing two team members, and the two turning up in the other group. But i so do not see this as a scam at all. For me the inquisition simply lacks the creativity and humour to pull a stunt like that. No, instead it's defiently alien in origin, and therefore off course heretic in nature and veeeryyy dangerous. Or just from the dawn of time and tehrefor heretic and veeeryyy dangerous. None the less its old, and therefore unstable. Which could explain why people just cant run around altering universes as they see fit. It only works once in a thousand, or million, or when the moon of some weird planet is in allignment with some otehr weird planet and on that day of days on that place of places things will become undone. Or redone as it is.

Or something.

Ok, I ran it with my group last Thursday, amid much groaning and Marvel comparisons. The Alternity Device was nicknamed the 'retcon gun' as soon as they found out what happened (which was pretty **** quick).

As for how it went down, the party had been sent downhive, under the supervision of Interrogator Hassan Instern, to investigate tales of a gang that had got its' hands on some xenos technology. They decided they wanted to do this subtly (after doing scary amounts of property damage on/to Ambulon, their Inquisitor warned them that if he heard one report of gratuitous explosions, he'd have Interrogator Instern execute them), and so requisitioned a hover-pickup truck as travel. (It is worth noting that in between the end of last mission and the start of this the psyker had undergone major surgery and been installed in a life-support vat, so their 'subtle' mission to the underhive involved a grav-pickup and a giant perspex tube with a mostly naked crippled midget inside...)

Having arrived in the settlement of Glory Hole, they decided to ask in the local bar (Herman's Hole) for any clues. There was much sniggering and immaturity about the names. Having gotten food-poisoning from the local moss ale, they interrogated one of the bar's patrons (Riley, owner and proprietor of Riley's Rat-birds and Information) and found out that the 'Black Skins' had been seen with fancy 'off-world' guns (although Riley had no idea that the guns weren't of human origin, and was so scared of the Black Skins that he refused to tell them any more). A critical failure on a Common Lore check left most of the party convinced the Black Skins were a pop band from the far side of the Malfian Sub (which in my campaign world is true, but the same name was used by an underhive gang in Sibellus, where the actual adventure was set).

While that miunderstanding was being cleared up, the psyker (whose vat was mag-clamped to the bed of the grav-pickup) spotted a group of local lowlifes, ne'erdowells and scummers eyeing the vehicle rather avariciously and, indeed approaching it while hefting weapons. He started a fight with his psychic schtick, and the resultant screaming and corposant got the attention of the other characters (in the bar), who came running out, and thanks to Distort Vision, broke a couple of noses on a vat-psyker they couldn't see. After a brief firefight, which scared off many of the 'innocent bystanders' (hehe), they captured two of the gangers. As they attempted to interrogate the prisoners, two other members of the gang showed up, attracted by the disturbance- one of which was the leader, carrying an avenger shuriken catapult, while the other bloke carried a large barrel-like device, with organic-looking ribs.
The players assumed the ganger with the Alternity Device was carrying some incredibly dangerous heavy weapon and did their best to hide from him and drive him into cover as quickly as possible... ignoring the man with the avenger long enough for him to turn Instern into Pedigree Chum. After that, some careful berserker charges quickly splattered the two bad guys- although the final stroke was from the arbitrator's shock maul... right to the primed Alternity Device.
One blinding flash later, the party finds themselves in a reasonably crowded street, with an intact Interrogator Instern, and a guardsman they have no memory of, and two of their number vanished. Cue out-of-character groans and comments such as "this isn't Infinite Crisis", and in-character reactions of WTF and quizzing the 'new' character as to what in the name of Him-on-Earth just happened (and likewise questions from the new character and Instern as to what they were on about).

The new timeline has them promoted, in slightly better shape (aside from insanity gained during the firefight), and summoned aboard the HDMS Magnus Ecthelion ready for Shades on Twilight...