Which Space Marine chapter would you want to see appear in a adventure? and why? As far as I know only one chapter has appeared in a FFG DH adventure and that wasn't a "Named" chapter.

Well, FFG has already developed their own Chapter, but as DH2 takes place in a different sector, it might be prudent to keep the Storm Wardens out of this after all. So if we're talking established Chapters, I'd say the choice should be based on the nature of the encounter.

And rather than the usual "SPESS MEHREENS TO THE RESCUE", how about basing an adventure around the Inquisition investigating the Chapter? Not only would this allow for an interesting excursion into the most private aspects of the Adeptus Astartes in general, it'd also be a refreshing exploration of the terrible idea of the Imperium's finest falling from grace. Of course, care should be taken not to have the end result affect the status of the Chapter as a whole -- but this fits nicely with the location being rather remote from the homeworlds of the most popular Marine groups, anyways.

Rough plot hook: A strike cruiser of the Flesh Tearers Chapter has approached an Imperial feudal-level world without stating intent and has been orbiting the planet for several weeks now. Attempts to hail the ship have remained unanswered, and earlier reports have led to rumours of the Flesh Tearers corruption beginning to spread through the ranks of the Inquisition. A team is dispatched to investigate the situation and ascertain why the Space Marines are there, the condition of the ship, whether they have landed troops on the planet, and if yes to what purpose.

Upon arrival, they notice that the ship still doesn't answer any attempts at communication. Should they choose to approach, however, a warning will be issued to stay away, threatening to open fire, after which the channel is cut again immediately.

Should they choose to approach further, however, the ship will not destroy them, but will not open its hangar bay to allow them to dock either. The Acolytes may try to forcefully board the cruiser via EVA, after which they find the interiors largely deserted, occasionally showing signs of a massacre on the ship's serf-crew. Confronting the skeleton crew of Marine officers will yield an explanation: several of the company's Marines have succumbed to their geneseed's curse as a long-term aftereffect of a prior battle, leading to a bloody insurrection between crazed and loyal Astartes onboard the vessel. All of the former and most of the latter have then relocated to the planet below, the former to sate their bloodlust and the latter to hunt them down and cover up the incident. As part of the cover-up, the Marine commander will then declare with honest regret but deadly finality that he cannot allow the Acolytes to leave as well, leading to a duel on the bridge.

If the Acolytes chose not to approach the vessel but instead land on the planet below, the game would shift to a more investigation-based playstyle as the agents have to ask around in villages and towns, investigating rumours of "ogre-knights" with armour impervious to the primitive local weapons, and who have started to hunt down the peasants on their fields, dragging their screaming victims off to their iron flying chariots. Depending on how the game proceeds, they might be able to make contact with the commander's XO who, rather than killing them as witnesses, asks the Acolytes for their help in putting his brethren out of their misery. The final combat encounter would be Marines vs Marines + Acolytes, where the human player characters must use their brains to counter the brawn of the berserk Astartes.

Regardless of the path chosen, should the PCs survive, the adventure would conclude with the Inquisition filing away yet another report on the downfall of this once proud Chapter, adding to a growing list of "incidents" which would ultimately culminate in their excommunication following the Third War of Armageddon in 999.m41. However, if the players managed to strike a deal with the Flesh Tearers' XO, they might chalk up a favour with Chapter Master Seth, and add the Flesh Tearers as a contact for the future as reward for keeping the secret (regardless of whether they actually do, or if they just say they would).

I was thinking something similar, players get to a site and find a 'Last Stand' by some SMs which should freak out the players to no end 'because if it can do this to SM what is going to happen to us'. Or in one of the codex's a chapter (the golden eagles/knights) got infected by Korn after fighting daemons for so long and became Korn followers. Imagine the players sent on a mission, maybe to pick up an artifact and notice the SMs starting to turn. Can they stop it? Can they escape if they can't? How fast can the Acolytes run? Can they become infected? What is the fear check vs a korn crazed space marine? Or Players on a mission the players find some space marines standing around a glowing pool. When they check on the marines it turns out the armor is empty. And then the pool stops glowing and the armor starts to move apparently on its own.

And rather than the usual "SPESS MEHREENS TO THE RESCUE", how about basing an adventure around the Inquisition investigating the Chapter?

Set your campaign early in the 41st century, and send the PCs to investigate the Rainbow Warriors chapter (from the very first edition of 40K), and have your players be the reason that chapter disappeared from 40K lore...

Lynata, I **** like your idea.

If you permit, I will take it, because I've got a player in my games that is more than enamoured with the blood angels, and his characters has contact with them. Seeing the problems of the descendants of the blood angel will clearly give him pause. It would be awesome. And the character is a high level templar calix, so he coud live up with the duel against the space marine commander.

Imagine the players sent on a mission, maybe to pick up an artifact and notice the SMs starting to turn. Can they stop it? Can they escape if they can't? How fast can the Acolytes run? Can they become infected? What is the fear check vs a korn crazed space marine?

This vaguely reminds me of an idea I pitched for a Deathwatch game some time ago; see the last point here . I think it'd be usable in DH as well, with minor adjustments..

I also really like the idea of the empty armour and the pool, tho! Suitably creepy.

If you permit, I will take it, because I've got a player in my games that is more than enamoured with the blood angels, and his characters has contact with them. Seeing the problems of the descendants of the blood angel will clearly give him pause. It would be awesome. And the character is a high level templar calix, so he coud live up with the duel against the space marine commander.

Absolutely! With such a character, that sounds like a lot of potential in terms of background synergy. Plus, it's not even just showing him the other side of the medal, but expanding the depth of his connection with both the good and the bad. Will he understand and appreciate the terrible choice the Captain had to make, will he be shocked at the dramatic extent to which the geneseed curse can affect the Marines' behaviour and reliability, and will this encounter lead to a deeper understanding between the character and his Astartes allies?

You should be PUNished for that, Lynata!

And rather than the usual "SPESS MEHREENS TO THE RESCUE", how about basing an adventure around the Inquisition investigating the Chapter?

Set your campaign early in the 41st century, and send the PCs to investigate the Rainbow Warriors chapter (from the very first edition of 40K), and have your players be the reason that chapter disappeared from 40K lore...

What happened to the Rainbow Warriors?

I probably should have started this under a different title. "in what way would you want SMs to appear in a adventure". How about the party finds a platoon or single SM of the Luna Wolves. Trapped in suspended animation or aboard a hulk that just reentered real space. And in the end has to decide if they should turn them in or not.

What happened to the Rainbow Warriors?

They were one of the original 10 Space Marine Chapters presented in Warhammer 40,000: Rogue Trader . Then they just... disappeared, never to be (officially) mentioned again.

http://wh40k.lexicanum.com/wiki/Rainbow_Warriors

They had a cool chapter symbol, but that name...!

I probably should have started this under a different title. "in what way would you want SMs to appear in a adventure". How about the party finds a platoon or single SM of the Luna Wolves. Trapped in suspended animation or aboard a hulk that just reentered real space. And in the end has to decide if they should turn them in or not.

Anything that presents the characters with a tough moral choice is a good way to play Dark Heresy, I think! The setting challenging our contemporary understanding of what is right or wrong is a huge part of what makes it work as an example of dystopian sci-fi.

They were one of the original 10 Space Marine Chapters presented in Warhammer 40,000: Rogue Trader . Then they just... disappeared, never to be (officially) mentioned again.

They were actually mentioned once more in WD #292 as part of the designer notes for 3rd Edition Codex Witch Hunters, though that was just a remark by Andy Hoare rather than an in-universe explanation:

"This gave us the basis for the character of the army - vengeful warrior-adepts tasked with enforcing the purity of other Imperial organisations. The Rogue Trader art even shows a Battle Sister exacting that vengeance upon a Space Marine, so this seemed particularly appropriate. In fact, the Space Marine is from the Rainbow Warriors Chapter, and as we haven't heard of them for some time, I guess the Sisters' mission was successful!"

On a sidenote, I recall some fan came up with a background that gave this Chapter a Native South-American (Inca'ish?) culture. I have a feeling that GW just thought of Greenpeace when they came up with that name, but this headcanon really makes the name okay in my book.

What about Space Marines as possible antagonists. Not "villains" persay, but perhaps the PC's have a particularly radical Inquisitor who's well.... radicalism rubs the Black Templars the wrong way (seeing how they're quite possibly one of the most overzealous chapters out there), and a small band of brothers is sent to make sure such radicalism is ended permanently?

Given how formidable Space Marines should be to the average party of Acolytes, such a campaign could be made of them doing everything they can to stay one step ahead of their relentless pursuers.

I like that, how about having to sneak into a SM base to get an artifact? Or going to a SM recruiting world to steal something during recruiting or kill/capture/get blood sample from a SM that maybe have been exposed/tampered with by a homonculus dark eldar. SM are notoriously arrogant and a black Templar wouldn't want to deal with a inquisitor who was a psychic or if he was in psychic prophesy.

What about trying to stop the Imperial Fists (my army) from building in a certain spot/planet?

"Blue on Blue" incidents are always funny, as they underline how good the Imperium is at messing with itself due to overlapping jurisdictions or casual disregard of official decrees due to sheer arrogance.

3E Codex Witch Hunters actually had a number of "plot hooks" for why the Inquisition would mess with a bunch of Space Marines:

• The Chapter's Chaplains are preaching an interpretation of the Imperial Creed deemed heretical, and the Witch Hunters attempt to call the wayward Chapter to account for its beliefs.
  
• It has long been suspected that certain of the Adeptus Astartes Chapters' gene-seed has grown debased and impure since the glorious days of the Great Crusade. The Witch Hunters attempt to gain a sample of the gene-seed, but the Space Marines aren't so keen to cooperate.
  
• The Chapter Master has unexpectedly manifested prodigious psychic powers, calling into question the psychic screening processes of the Chapter. The Witch Hunters cannot allow an entire Chapter of rogue psykers to come into being and resolve to wipe them out before it's too late.
  
• The Chapter's Librarians are able to call upon psychic powers unseen in those of any other Space Marine force, leading the Ordo Hereticus to believe that they are trafficking in knowledge no loyal servant of the Emperor has any right delving into.
  
• Many Space Marine Chapters are notoriously independent, and often follow their own agendas with little or no recourse to Imperial policy. One such Chapter has refused to give aid when requested, resulting in the loss of a strategically vital world, and the Ordo Hereticus resolves to bring the Chapter Master to justice.
  
• The Chapter recruits its aspirants from a feral world, and it has recently been discovered that the natives' gene pool is subtly but irreparably corrupted and has been for millennia. The Ordo Hereticus is not prepared to risk that the Chapter may have inherited the mutations of its homeworld.

Note that this presents only the perspective of the Inquisition -- it wouldn't be hard to actually find an understandable reasoning for why the Marines have acted the way they do for most of these situations. For example, perhaps they see their Chapter Master's newfound divination powers as visions from the Emperor, or the Chapter that refused to give aid when requested was unable to do so due to having suffered too many casualties in a prior battle, or they are simply both innocent and proud and thus refuse to submit to genetic testing even though they are "clean", thus triggering a lethal response by Imperial forces ... the list goes on.

It's all about the coin having two sides. Or in this case, a story having two versions.

Champions of the Emperor - no wait, that's my homebrew one...

Marines Malevolent so I can kick their arses.

Every chapter involved in the Badab uprising, especially the Mantis Warriors

Scythes of the Emperor, Celestial lions . Why do the cool ones always die?

I was gonna say Space Sharks , but we already have the Carcharadon Astra so that's close enough.

Also the Invaders because I made the BFFs with one of my other homebrew chapters.

Most chapters back stories give good reasons to incorporate them into a DH2 without much effort.

In addition to mentioned above, the Dark Angels could work. A Chaos space marine is wreaking havoc in the region and causing uprisings (unbeknownst to the acolytes he is a fallen angel). In investigating the crimes their trail coincides with a squad (or less) of Dark Angels also pursuing the adversary. Whilst it would seem that they should help each other the group finds the SMs to be most unhelpful with an attitude almost to the point of hostility. Should they get too close to finding out the secrets of this nemesis they may find the Dark Angels to be a greater threat to them than said CSM.

And you've always got the good old Relictors on their never ending quest for profane relics to use against Chaos. They may be potential enemies for puritans and potential allies for radical (or still rivals, this is the Imperium after all).

And yes Lynata you are right about the Rainbow Warriors, they were originally named in tribute to the Greenpeace vessel The Rainbow Warrior. Like many things with GW though the lore may have changed quite substantially over time.

In addition to mentioned above, the Dark Angels could work. A Chaos space marine is wreaking havoc in the region and causing uprisings (unbeknownst to the acolytes he is a fallen angel). In investigating the crimes their trail coincides with a squad (or less) of Dark Angels also pursuing the adversary. Whilst it would seem that they should help each other the group finds the SMs to be most unhelpful with an attitude almost to the point of hostility. Should they get too close to finding out the secrets of this nemesis they may find the Dark Angels to be a greater threat to them than said CSM.

I vaguely recall the DA already clashing with other Marines and the Inquisition in their quest to cover up their past -- their background really lends itself well to this sort of situation.

Party finds SM during adventure to find where weird stuff is coming from, SM request help from inquisition Acolytes . Missions for SMs are odd (steal holy artifact from shrine, kill town mayor, destroy vox relay station, etc.) Party finds out that SM is actually Alpha legion, plotting bad things. Party must fight or join AL. (it has always bugged me that AL are these great infiltrators, and spies, "Have you seen any nine foot tall men in power armor around here lately?")

(it has always bugged me that AL are these great infiltrators, and spies, "Have you seen any nine foot tall men in power armor around here lately?")

That's just how good they are

Players are sent to recover an artefact, probably some ancient space marine weapon. But some humans also show up to try and acquire it for themselves, including stealing it from the acolytes if they can.

As the acolytes piece things together they will figure out that these humans are serfs of a space marine chapter. Specifically, serfs responsible for making sure that the Space Marines are properly supplied. These specific serfs belong to the Blood Ravens.

Do the PCs gift the artefact to the Blood Ravens or start a fight with them ?

I like that, How about 2 chapters show up and want the same artifact that the Acolytes have found.

They were one of the original 10 Space Marine Chapters presented in Warhammer 40,000: Rogue Trader . Then they just... disappeared, never to be (officially) mentioned again.

Not true - they are officially mentioned in the Deathwatch Audio Book Mission:Purge by Gav Thorpe...

There's a Black Shield in that book who refuses to state his origins (as a lot do). The Space Wolf's main source of amusement whilst on mission is needling the Black Shield by trying to guess his chapter. One guess is:

".....Is it the Rainbow Warriors? If that was my chapter, I'd want to cover it up too..."

".....The Rainbow Warriors are proud and noble sons of Gulliman!"

".....Yes, but it's the name ."

I like the idea of poking around in a chapter's domains. There is an entity - the Ordo Astartes - listed in Codex:Inquisition with responsibility for just that, and throne knows enough chapters have a Dark Secret hidden somewhere.

There are plenty of opportunities for something like this, with loyalist or less loyal chapters. The lead-up to the Badab War is a mess of miscommunication and conflicts of (quite valid) interests. I've had Deathwatch missions where a remote and covert Watch Station comes to the attention of and is misinterpreted by the Dark Angels as a Fallen holdfast.

Equally, an astartes homeworld is an interesting place to be poking around in for the more 'conventional' threats - cults, xenos infiltration, etc. There is a story about an Ultramarines successor chapter (I forget which one) destroyed by the Alpha Legion by suborning and brainwashing the best and brightest of the planet's hive gangers - the ones who would then be selected to become astartes neophytes and later battle-brothers. Equally, a genestealer cult getting lose on any imperial world is scary, but on an astartes world scarier still!

None, because unless the game involves PC's who are Astartes I try to keep them as far away from my games as possible, unless Chaos Marines are some sort of antagonist and even then it's usually lone individuals.

Now that I think about it, do we have any fluff on Space Marines in Askellon?

The sector is mostly cut off from the outside Imperium, so I can't imagine the imperium would intentionally SEND them there. It's not unlikely that chapters might go there independently to search for specific relics or tracking a foe.

But do any chapters actually have a standing presence? The Calixis sector had the Storm Wardens, so the question arises as to whether or not Askellon also might be home to a native chapter or two.

That said, the Askellon sector has a much smaller scope than Calixis. Askellon is mostly a few very populous, very ancient worlds holding out against inevitable doom. Having an entire chapter based in this region almost seems unrealistic.

If they have an entire chapter protecting this handful of worlds then things shouldn't be as bad as they are.

However there must obviously be at least some Space Marine presence if we can recruit Deathwatch marines as reinforcement characters.

Having an entire chapter based in this region almost seems unrealistic.

Why is that? Lots of chapters are ancient organisations that dates back from millenia. Askellon wasn't necessarily THAT backwater then. They could also have been organised there because the Imperium thought there would be a lot more expansion in the region, and then, it was forgotten or the project of expanding the Imperium in this region stopped, leaving a Space Marine chapter homebased there.

Anyway, it's not as if Space Marines hadn't the means to go fight elsewhere if needs be.