I have a copy of the Dark Hersey book from when it was published by Black Industries. How compatable is that book with the rest of the line being done by Fantasy Flight. Also how compatable are these rules with the Rouge Trader and Deatwatch lines? Is it possible to run a game with characters from the three books? If so which ones mix and match best?

Its the same book, no differences. The other books are different power levels/ranges. RT is meant for a much more epic range than DH, as you are Rogue Traders in command of your own ship that you can do with whatever you wish. RT characters are going to generally have higher stats but lower skill ranges than equal level DH characters, that said, RT characters start on about the 4,500XP range of the advancement chart.

DW is focusing on the Space Marines (well, Deathwatch), and as such its going to be even higher thematically. Power level is much greater than DH, and I cant recall the exact XP equivalent they start with (nor do I feel like checking, but they are high in the charts). They are combat monstrosities but they dont Investigate well (at least not in the same sense as a DH acolyte).

Any of them can be mixed and matched, and they provide rules and suggestions on how to do it, but doesn't mean every GM will just let you pop in. The problem comes down to the different focuses of the lines, as well as the general fluff.

Make sure to check the errata that FFG made for the DH book, it fixes a few of the broken rules. You can download it from the official DH page here on FFGs homepage.

There are some small rules changes across the system.Psychic Powers are handled completely differently in Dark Heresy than in Rogue Trader and Deathwatch. A couple of the Talents work slightly differently, and Righteous Fury is different in Dark Heresy, and even after the Errata and FAQ there are some other very slight differences. However, the core of the system is identical, and much of the material is interchangeable. Equipment, stats for adversaries etc are pretty much usable in all 3 games, regardless on the system the book is specifically published for. The one major exception is (as mentioned) Psychic Powers, and there are some minor niggles with stuff like equipment (Rogue Trader equipment has no money cost listed, meaning you have to come up with your own price if you want to use it. Dark Heresy stuff can easily be used in Rogue Trader though as Rogue Trader uses the availability to determine if they can get it, which is still listed).

Kael said:

Totally possible. The GM just has a little extra work on their hands in order A) Create a setting and reason for the players to be together that is compelling and B) creates adventures in such a way so as to let each of the characters have their bit of screen time. While that's what you should do in every campaign, those two points become a bit more challenging when merging DH, RT, and DW.

IMHO, the three games are as compatible as were White Wolf's games in the previous World of Darkness.

DarkLoic said:

I would say 40k games are MORE compatible with each other whan White Wolf WoD games, by a long shot.

Charmander said:

I think I have to disagree with you, mainly because :

- PC are not well balanced from one game to another.

- Rules to get gear are very différent and not really compatible, IMO.

- There are other specific rules that could seem easily forgetable, at first sight, but increase the two drawbacks/flaws above, like Hordes in DW or Psychic Rules that are not designed to work together between DH and the other games.

DarkLoic said:

I'll say I've NOT run crossovers myself, but the paperwork SEEMS to me to indicate that DH ascended characters are close to DW characters are close to mid level RT characters. Each has their specialization, and this is where the extra GM work comes in (and the extra work is considerable), in creating compelling encounters that keep the whole troupe involved, interested, and alive.

DarkLoic said:

DW does cover some of this in a sidebar, it discussed their req system and how to integrate it into the other two systems. It appears to be compatible to me.

DarkLoic said:

Psychic rules I will totally give you; in general as I find them very...odd. Hordes are compatible with DH and RT, it's just that DH and RT characters aren't designed to be the combat monstrosities that DW characters are designed to be, and so aren't equipped as well to deal with them. But at the same time, things like that are simple encounters that can be used or not, they're not a mainstay requirement of the game.

In WoD, Mages trump everything in the last two versions. Vampires rule in the currend incarnation and Werewolves were more dominant in the previous one. Side by side, xp for xp, starting character to starting character, there are tremendous differenses in the supernatural powers, and those powers are what make you 'special.' I have run rossovers in WoD games, and most of them end with the fish out of water player getting obliterated or left out.

Charmander said:

Here , somme examples of how PC from each game could be at 50 000 PX.

DarkLoic said:

Fair enough, looks like it's a rough go for a GM regarless of what game you try and crossover these days

Interesting thread!

I have DH & RT, but haven't gotten DW yet. I had an idea for a campaign where the players have more than one character each: an Ordos Xenos acolyte and a Deathwatch SM. The idea being that an Inquisitorial investigation by their DH PCs might lead to their Deathwatch PCs being called in as a strike team. Does this sound possible to do?

Of course it is !

However, it must be carrefully planned, IMO.

Otherwise, it could become far to predictible and boring.

In part, because DW characters are killing machines much stronger than acolytes.

DarkLoic said:

Well, for starters it would probbly be a one-off adventure. But I agree re: extended play. I don't think it could follow the same progression every time. (Investigation>Strike Team) without getting repetitive.

bighara said:

One of my concerns aside from repetition is DarkLoic's point about DW characters being so much stronger- specifically in early acolyte levels, DW Marines will simply outclass the acolytes, which may lead to feelings of players not wanting to play their 'inferior' DH characters, and potentially missing some of the RP elements that are present in DW.

I think you just need to be careful and plan out your adventures in a way that gives each 'version' a unique feel to keep the interest high.

As a one off, the biggest concern I'd see is players wanting to get their hands on the superior astartes gear

Charmander said:

Hmm, interesting points.

I guess I'm picturing a sort of "hand-off" where the acolytes manage to uncover the critical information, i.e. the xenos' location or target, then call in the strike force. At that point the SMs take over and the DH characters aren't really involved. Almost like switching from one campaign to another, but with related events.

Another possibility is to have the acolytes trying to find some piece of the puzzle in one area while the SMs are blasting the bejeebus out of xenos in some other area (different parts of the "battlefiled" -or even on different worlds!). The plots are related, but not identical.

I'll have to ponder.

It should be noted that DH, RT and DW all have different foci and auxiliary mechanics that were taken into consideration when the careers were created. The easiest example to understand is Rogue Trader.

Simply put, each character is assumed to have nearly limitless resources, and access to a third, party attritube of Profit Factor. RT characters don't keep track of individual thrones, nor do they really have to work to get great equipment; they don't sweat outfitting their private regiments, much less getting a single trinket for themselves, and they've got their own ship (or ships).

Separating a RT character from these resources removes a huge facet of their powers and makeup.

Along the same lines, a DH character with alot of focus in investigative skills isn't going to be of much use without an opportunity to use these skills. And the Deathwatch marine will blow them both out of the water when it comes to combat, even if they're scaled to the same level, because that's all a DW marine is supposed to do.