I'm a new DM, and I'm not really familiar with a lot of the existing adventures and not super confident with writing an original homebrew campaign. My new group that's interested in starting a campaign is looking for something grimdark along the lines of Bloodborne, Darkest Dungeon, and Remnant. Any recommendations?

Of the official 5e adventures, Descent into Avernus is probably the most grimdark one out of the box - you go into the first of the nine Hells, make some deals with demons, and drive some Mad Max-inspired cars.

Personally, however, I find it to be a pretty bad campaign - it is very linear and basically little more than a glorified fetch quest.  There are plenty of people who like Descent into Avernus though, specifically because of this on-the-rails play, so if that is something you and your players might like, feel free to disregard this warning.

You could probably make something grimdark out of Icewind Dale - the setting is certainly bleak enough.  But Icewind Dale is not an easy campaign to run out of the box, and if you do not want to homebrew, it is not a campaign for you. It has a thin plot, no real characterisation to its BBEG, and huge pacing issues—it is basically a sourcebook for Icewind Dale (which it does very well at) masquerading as an adventure, so the DM needs to do a lot of heavy lifting to make something palatable.  In fact, it is bad enough D&D Beyond made an entire article once which basically boiled down to “Oops, Wizards forgot to make the bad guy interesting - here are some supplemental ideas.”

I have no personal experience with the Dragonlance campaign, so cannot speak to its quality, but it has plenty of art which could lend itself to the grimdark, and is set during an armed conflict, so you likely could do something with that campaign.

Another option you have is to look at earlier editions and adapt content to 5e (which can often be as easy as finding similar monsters and using those, and adjusting how non-combat checks are done).  Dark Sun, for example, was designed as a grimdark setting, full of liches, fights over limited resources, slavery, violence, etc.  

Lastly, you could always try to homebrew something - if is less intimidating than folks seem to think, and there are plenty of helpful folks here on Beyond ready and willing to help if you need a hand.

DM Workshop in the DMG has suggestions on grim and gritty systems to use to help give more of a grimdark edge.

Anything can be grimdark with a bit of effort.

I mean, the entire genre got its name from Warhammer 40k, and the games mentioned and novels like the Game of Thrones series have only pushed it along.

So, let's look at the primary concepts:

• Morally ambiguous characters
• A bleak and brutal place
• Graphic depictions of violence and gore
• A dystopian location
• An emphasis on realism, even when set in a fantastical world

So, first off, using the last bit, you are going to use "gritty realism" rules and ruling style (DMG).

All the characters in a module (even the free ones) can be added onto with more stuff about them hinting at the moral ambiguity.

Gore is a descriptive aspect -- you can talk about fountains of blood and entrails and guts everywhere during any combat encounter or any time some finds something gross. You can also mention how blood itches like hell and how the smell is bad. Always, always amp up smell in grimdark situations.

FR is not very good as a dystopian setting as a whole. Some parts of it are (Chult), but most of it is just fairly standard stuff.  You could, ahem, locate this in a barren and bleak desert ruled by despots who rigidly control water and food and force people to struggle for everything. Or any of dozens of other options. Bleak means a place without hope, brutal is essentially saying there will be damage, and even an easy encounter is going to be pushing the CR level of the Party as a whole.

The games noted make frequent use of art as a part of the overall atmosphere -- and D&D doesn't have a lot of that kind of stuff anywhere for visual impact. personally, I can't think of anything, but I am not personally familiar with every book or image put out for 5e.

I would argue that Tomb of Annihilation is a comparatively easy one to do this with -- but it is a jungle style start.

I have no familiarity with their published campaign but like many people I really enjoy the Dungeon Dudes' Youtube streams.  The Dungeons of Drakkenheim adventure they developed might be interesting for you to check out.  It seems to have had mostly positive reviews.

https://ghostfiregaming.com/dungeons-of-drakkenheim/

Quote from Caerwyn_Glyndwr >>

You could probably make something grimdark out of Icewind Dale - the setting is certainly bleak enough.  But Icewind Dale is not an easy campaign to run out of the box, and if you do not want to homebrew, it is not a campaign for you. It has a thin plot, no real characterisation to its BBEG, and huge pacing issues—it is basically a sourcebook for Icewind Dale (which it does very well at) masquerading as an adventure, so the DM needs to do a lot of heavy lifting to make something palatable.  In fact, it is bad enough D&D Beyond made an entire article once which basically boiled down to “Oops, Wizards forgot to make the bad guy interesting - here are some supplemental ideas.”

Rime of the Frost Maiden also tried to be grimdark and silly and whimsical at the same time and as a result really failed at both.

Quote from 6thLyranGuard >>

Quote from Caerwyn_Glyndwr >>

You could probably make something grimdark out of Icewind Dale - the setting is certainly bleak enough.  But Icewind Dale is not an easy campaign to run out of the box, and if you do not want to homebrew, it is not a campaign for you. It has a thin plot, no real characterisation to its BBEG, and huge pacing issues—it is basically a sourcebook for Icewind Dale (which it does very well at) masquerading as an adventure, so the DM needs to do a lot of heavy lifting to make something palatable.  In fact, it is bad enough D&D Beyond made an entire article once which basically boiled down to “Oops, Wizards forgot to make the bad guy interesting - here are some supplemental ideas.”

Rime of the Frost Maiden also tried to be grimdark and silly and whimsical at the same time and as a result really failed at both.

 I would go with that one, then. 😜

Quote from AEDorsay >>

Anything can be grimdark with a bit of effort.

 

 My Little Pony. Go! 😜

Quote from DoveArrow >>

Quote from AEDorsay >>

Anything can be grimdark with a bit of effort.

 

 My Little Pony. Go! 😜

 If you think that's a challenge, you've never tried Fallout: Equestria.

As mentioned above, TOMB OF ANNIHILATION is probably the best option of official WOTC material for a grimdark campaign. BG:DIA has the bones of what could be something pretty grimdark, but it'll require a good deal of customization by the DM to get there. (Despite the adventure literally going to hell, the book explicitly says Avernus essentially functions as a foyer to the Nine Hells, and doesn't feature souls in torment or any other classic hellish elements. So the DM would need to do some work on making it a grimmer, darker place.

I'd recommend doing some browsing on DMsguild - there's a whole series of FR "remixes" that use the premise of "What if Vecna, Tiamat, etc. won?" I haven't read or played them, but they're very well reviewed. The titles are Doomed Forgotten Realms, Academy of Adventure, Rise of Vecna, Fall of Vecna, and Reign of Rot.

There are also some very good OSR products that are firmly in the grimdark category but they all would require fairly extensive conversion efforts to serve as 5E campaigns or adventures.

Quote from DoveArrow >>

Quote from AEDorsay >>

Anything can be grimdark with a bit of effort.

 

 My Little Pony. Go! 😜

 
Applejack staggered into the cavernous building, limbs aching, the taste of ash and the smell of blood a haze that would not let go.

"I told them there could be only one"...

----

I know nothing about MLP, and had to google the name for one of them, lol. But I already know there are folks who took MPL and carebarsand similar and went full on grimdark witt hem because of that exact kind of challenge.

I mean, we live in a world where everything can become a **** set up (so much so there is a rule about it) and you think it would be hard to go grimdark?