A downloadable module

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THE MARTIAL CULT OF BLOOD KNIGHT GAIUS is a 20-page dungeon crawl about a religious order of vampires who deny their feeding urges, instead only drinking the blood of those whom they have given a formal chance to defend themselves. 

The spells, items. and monsters described in this zine are intended for use with Ben Milton’s Knave, but can also be quickly converted for use with B/X or other OSR derivatives. In this zine, you'll find:

  • NINE MONSTERS AND NPCS: Encounter feral and ravenous Mad Vampires, cyclopean Mountain Screamers, dashing and flamboyant Vampire Knights, a foolhardy adventurer called Sycorax, the craven and backstabbing Demon Priest Morpho, and more!
  • TWO HARD-HITTING BOSSES: Compete in a duel for a fabulous reward with the brooding cult leader Blood Knight Gaius, and encounter his bodyguard and trusted companion, the mysterious giant First Disciple Matsunaga.
  • EIGHT SPELLBOOKS AND ENCHANTED ITEMS: Steal Matsunaga's limb-cleaving claymore, wear the Blood Knight's cloak of stars, and gain crystal-control over the Demon Priest Morpho. Read from the spell tomes of the Monastery and learn to summon a full moon, turn the floor into a sea of fire, become a classic movie vampire, and forge a blade from your own blood!
  • EVEN MORE OSR GOODNESS: Build tension with a rumors table about Matsunaga, set the mood with passages of prose to read to your players, flesh out the story with four reasons to visit the Cult and three possible Epilogues, map out the Monastery courtesy of watabou, and gaze upon three full-page illustrations by yours truly!

While the tone of the adventure is meant to be pulpy and spooky, prominent themes include religion, starvation, shame, blood, and slight body horror. Please confirm that each of your players are comfortable with these themes before you play!

In a previous version of the module, I suggested players listen to an album by Old Tower. I have been informed that Old Tower is associated with Nazi black metal acts. Please do not purchase, stream, or support the music of Old Tower. Check out ...and in the autumn night the black castle rose by Draped in Shadows instead!

On page 10, the final random encounter is First Disciple Matsunaga, with no information about the encounter. Guidelines for how to handle Matsunaga randomly appearing in the dungeon are listed on the two-page spread addressing the character.

CategoryPhysical game
Rated 4.9 out of 5 stars
(30 total ratings)
GenreRole Playing
TagsDungeon Crawler, Horror, Magic, OSR, Tabletop role-playing game, Vampire
Asset licenseCreative Commons Zero v1.0 Universal
Average sessionA few hours
AccessibilityColor-blind friendly, High-contrast


Buy Now$5.00 USD or more

In order to download this module you must purchase it at or above the minimum price of $5 USD. You will get access to the following files:

BLOOD_KNIGHT_GAIUS_playermap.png 313 kB

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Development log


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The cover states the book is meant for Basic and Expert rulebooks - what rulebooks is it referring to? Apart from Knave, of course, but I can only see one book for Knave.

this refers to the original Basic and Expert D&D Rulebooks!

BLOOD KNIGHT GAIUS was featured in Episode 33 of Splinterverse's D&D New Releases series!

Here's an unsolicited review for ya:

To anyone interested, this is an absolutely charming module and well worth picking up. Totally top notch stuff here.

Hey Claymore, I ended up porting this to my own game have run it twice now.  I loved how the randomized encounters made things totally different for each group and I appreciated that while the mood of my games was pretty tongue-in-cheek, it could easily be spun into something pretty darn pulpy or even given a serious tone.

thanks for the review, I'm glad you like it!!

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I never really had the urge to DM before (or GM depending on the game) but after reading into this I was absolutely stoked and really wanted to DM this as a one shot. I'll be porting it over to DnD and might take a few creative liberties but this concept really intrigued me. Got the minis done and read through it all, time to fully create each character and design the set in Tabletop simulator!


omg that's awesome!!! 

I love concepts that don't always fit the norm, like a cult of vampires who fast/ have honorable duels, making a Jedi into a DnD character, etc. Love that stuff! Love this concept, love your work! 

I love this! I'm preparing a D&D campaign based on this rn, can't wait to play it soon :]


that's so cool!! not sure if it'll materialize but I have some notes for a sequel called The Manse of Matsunaga 👀

I'd love to see that.... Matsunaga caught my interest before and now I'm even more curious


Fantastic adventure! For a review, head here: https://podofblunders.com/2021/10/22/the-martial-cult-of-blood-knight-gaius/

thanks so much for the review !! one question: are werewolves equivalent to dwarves 🤔


Hmmm they're hairy and like the dark, but not greedy or short. Also, dwarves love precious metals of all sorts but werewolves aren't fond of silver. 

Still...the comparison feels right...

This seems very good! Is there player's map without keys and secret indications for use in a virtual tabletop software?

i didn't even think to make one but this is a great idea!! just finished the player map and uploaded it to the game files, hope it helps!

Well, that was fast! Thanks, it will be useful for sure.


Sweet! Will there be a print version?

possibly ! it doesn't seem like people are very interested in it (only got 20-odd upvotes on r/osr, no replies on rpg.net so far) so i probably won't do a physical run unless a lot of people want one. maybe i'll do print on demand from lulu or drivethru though !! 


bit of a surprise but exalted funeral picked it up! https://www.exaltedfuneral.com/products/the-martial-cult-of-blood-knight-gaius-p...

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The Mortal Cult Of Blood Knight Gaius is a low-level adventure designed for use with Knave or B/X (although it feels very easy to adapt to other osr.)

This is not the first thing you'll notice about it, however.

The first thing you'll notice is the striking art and graphic design.

Blood Knight is stark and grimy, and I basically felt ambient synths start playing in my head when I opened it up.

The PDF is 20 pages, and the adventure within orbits around its central character: the vampire Gaius. Gaius has a *strong* gothic vibe, being torn between his noble goal and his sanguine desires, and in general the adventure presents the vampires are tragic monsters---with emphasis on both the tragic and the monster.

That said, the module's setup is a fairly hard subversion of all other vampire modules I've seen. The PCs know going in that Gaius and his cult are vampires, but the vampires aren't automatically dangerous to the PCs. Their whole deal is about denying their urges and only killing with permission, and they're genuinely good hosts if all you want out of the adventure is an eerie, tense place for the PCs to rest in perfect safety.

If the party wants to treat the dungeon like a regular dungeon, they absolutely can and the module is formatted expecting this, but there's a fair amount of attention in the room descriptions paid to the way the vampires' cult works on a day to day basis. If you go full violence from the jump, it'll feel a bit like you're dungeon-crawling someone's home---and that alone would sell me on it, but there's more.

The module includes an excellent dungeon map, unique spells, interesting NPCs that the players nevertheless aren't forced to interact with, multiple ending conditions, and the text sticks its gothic tone right up until the last two pages when it gets slightly cheeky.

Overall, I think this is one of my favorite osr adventures. It's easy to drop into a campaign, it's well-written and atmospheric, the players set the pace through it, and the players decide which aspects of it to engage with. Even without the impeccable art and layout, it would still be versatile and easy to use, but as a complete package it is a huge value-add to your old-school adventure library. I strongly recommend getting it.

Minor Issues:

-Page 10, First Disciple Matsunaga's entry seems to be cut off here.


thank you so much for this review !! i'm really glad you liked it - i'll fix the minor issue with matsunaga; my intent was for GMs to reference their character page for how to handle random encounters, but i'll make this more clear!


BLOOD KNIGHT GAIUS is one of those perfect little OSR modules. Settle into your chairs around the table, lay your drink-stained character sheets before you, and stare up at the towering GM screen as candles of red wax are lit.

The concept is immediately strong; a sect of monk-like vampires feed only on those who search for them and fail in honorable combat. If you win, you take an inordinate amount of money back home, and if you fail, well... you knew the risks. It effortlessly combines the tone of spooky-Dracula vampirism and old martial arts film and anime. 

The layout, graphic design, and art of the module is both simple and impeccable, the scantone quality of some pages and towering silhouettes of its primary foes adding much to the mood. 

Situations present themselves that don't necessarily have to be resolved through combat, making for a complex OSR experience. The snippets of lore and little touches present throughout are very evocative and should be shown to the players at any opportunity. 

It's really good, basically. I love thematic, punchy modules like this one. Ascend the mountain and challenge BLOOD KNIGHT GAIUS, for the night is long, and glittering gold awaits behind a cloak of stars. 


thank you ripley !!