The Warhammer 40,000 Summer Fest Exchange is back for 2026!
This fandom event is a Warhammer 40,000/Horus Heresy-focused gift exchange for fanart and fanfiction, hosted on AO3 – you can see previous years' gift collections here: 2022 | 2023 | 2024 | 2025.
Sign up to write a fanfic or create a piece of fanart, and receive a story or artwork in return!
Schedule:
May 15–May 31: Nominate your favourite characters and pairings
June 1–June 14: Sign up for the exchange
June 14–June 15: Matching and assignments go out
August 2: Assignments due – deadline countdown
August 15: Works go live (unless delayed for pinch hits)
August 22: Creators are revealed; the collection will remain open for treats
All deadlines are 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT.
👉 You must be 18+ and have an AO3 account to participate.
For information on how to sign up and participate, see the AO3 exchange profile.
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We hope you're all having fun with your Summer Fest assignments! We already have 27 finished gifts and treats in the collection, with more drafts on the way. 🙌 Do you think we'll reach 100 works this year? 🤯
⏰ Assignment deadline: Two weeks to go!
Reminder that assignments are due on Sunday, August 2, at 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT (deadline countdown).
🌎🦅⭐ Psst! Americans! Please note that this is Sunday morning for you. ⭐🦅🌎
If you haven't submitted your assignment yet, now is a good time to make sure you're on track.
If you already know you won't be able to finish your gift before the deadline, please default as soon as possible so we can arrange a pinch hitter for your recipient.
Defaulting: Important info and step-by-step guide 👇
If you expect that you won't be able to complete your assignment on time, simply use the Default button on AO3.
You don't need to explain why you're defaulting. We know real life sometimes gets in the way of even the best intentions.
To default, go to your AO3 profile, click Assignments in the left-hand sidebar, and click Default under your assignment.
🤔 I don't know if I should default?
Remember, this is meant to be a fun, low-stakes exchange. The minimum requirement is just 500 words or one finished sketch.
If you've planned something bigger than you can realistically finish, consider creating a smaller gift to fulfill your assignment first. You can always post your magnum opus later as a stress-free treat!
However, if you're dealing with a real-life crisis, a medical emergency, or other unforeseen circumstances, please let us know as soon as possible so we can help. ❤
😥 What happens to my recipient if I default?
If you default, we'll post your assignment here on tumblr and ask for a volunteer pinch hitter to create a gift for your recipient instead.
The exchange collection won't be revealed until every qualifying participant has received a gift.
😩 What happens to me if I default?
If you default on your assignment before the deadline and your assigned creator also defaults, we won't delay the collection reveal for you, but we will post you as a pinch hit recipient.
If you no-show at the deadline without defaulting, we'll post your assignment as a pinch hit without further notice. If your assigned creator also defaults, your own assignment will not be posted for pinch hitters.
There are no other penalties for defaulting – but the mod team will be sad 😢 and gift reveals may be delayed for everyone, so please be considerate.
💝 Have fun creating!
Already finished your assignment? Check out the other requests and see whether any inspire you to create a treat. 😎
Yes, you're very welcome to create two works for the same request. 🙂
If the works are for your assigned recipient, one must be submitted as your official exchange gift and meet the exchange gift requirements (guide to gifts), while the other should be posted as a treat (guide to treats). This ensures that AO3 correctly registers your assignment as fulfilled.
You're welcome to create as many treats as you like, whether for the same recipient and request or for different recipients and requests. 🙂
Hey! So I finished the text of my work way earlier than I thought I would. In addition to some treats as the muses permit, I thought I'd also make a podfic for my main gift work (note that this is in addition to, not in place of).
I've left the usual podficcer-identifying metadata off of the podfic; however, an important question:
Can I just include the podfic (whether after the fic text or as a second chapter)? Or should I wait until after creators are revealed to post/share the podfic?
Thanks!
Thank you for your patience while we considered your question. As we have never had a podfic in the exchange before, we wanted to discuss it as a mod team before making a decision.
Our main concern is that audio is not one of the media offered by this exchange, and we are mindful that some participants may not be able to access audio media and might have opted out of it at sign-up if given the choice. On the other hand, we do encourage participants to have fun and get creative with their gifts.
With that in mind, we have decided on the following options:
You may include a podfic as bonus content attached to your gift fic, i.e., after the text or in a separate chapter, provided that it is anonymised as much as reasonably possible.
Alternatively, you can post the podfic as a separate work once the anonymous period has ended.
We hope one of these options will work for you. If you have any further questions, please don't hesitate to contact us. 🙂
hey! question regarding treats; do they stay hidden until reveals, or will they be visible right away?
Treats submitted to the exchange collection will work the same way as gifts. They will remain hidden until the collection is revealed on August 15 (or later, if reveals are delayed due to outstanding pinch hits), and their creators will remain anonymous until the creator reveal one week later.
Our guide to treats explains how to submit them to the collection. 🙂
Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
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Free to watch • No registration required • HD streaming
There were no Initial Pinch Hits this year. Participants have been very generous with their offers, so we successfully matched up everyone.
Speaking from experience, though, there will likely be some regular pinch hits during the creation period and after the assignment deadline. We'll share them here on tumblr, and would very much welcome your help getting them filled. 🙏
You're also very welcome to post treats to the exchange collection. There's a guide to treats here.
WH40K Summer Fest Exchange: Bookmark your favourite prompts for treats
Courtesy of fourgods-nobrakes:
The AO3 Automagic App also gains a new feature now that signups are closed, for anyone who wants to go through the prompts and make a treating list! You can now bookmark individual prompts. Click the heart at the start of any individual prompt:
and that prompt will now show up on the "Bookmarks" tab.
Note that this is done with cookies, so the list won't transfer from one device to another. Hoard all your prompts in one place!
Found a request that inspires you? Want to surprise someone who deserves a little something? You can make a treat!
Treats are extra gifts submitted to the exchange outside of your assignment.
How treats differ from assignments:
You do not need to be signed up for the exchange to create a treat. Anyone is welcome to create treats for requests in the exchange.
You may create treats for any participant, as many as you like.
You do not need to ask the mods for permission; just create your work and submit it to the collection.
Treats do not need to meet the minimum assignment requirements. They may be shorter than 500 words, sketches, or other smaller works.
Treats must follow the recipient's stated Do Not Wants (DNWs).
There is no deadline for treats. The collection will remain open after reveals for late treats.
The Automagic AO3 App is a great way to browse requests. Simply search for a character or relationship to see all matching requests in the exchange.
Submitting treats: Step-by-step guide 👇
First, find a request or participant you'd like to create a treat for. You can browse requests through the Requests Summary or the Automagic AO3 App.
Once your treat is complete, go to the exchange profile page and click "Post to Collection":
You will be sent to a Post New Work page that is already set up with the WH40K Summer Fest collection.
Things on this page should be pretty self-explanatory. See also the AO3 tutorial for posting a work.
⚠️ Exchange-specific requirements
Ratings
Your work must use one of the following Archive Ratings:
General Audiences
Teen And Up Audiences
Mature
Explicit
Works marked "Not Rated" will not be approved.
Archive Warnings
Your work must use the appropriate Archive Warning:
Graphic Depictions of Violence
Major Character Death
Rape/Non-Con
Underage Sex
No Archive Warnings Apply
Choose Not To Use Archive Warnings
Important! Note the difference between the two non-specific Archive Warnings:
👉 No Archive Warnings Apply means the work contains none of the four major Archive Warnings. Other potentially sensitive content may still be present and should be tagged appropriately.
👉 Choose Not To Use Archive Warnings (CNTW) means the work may contain one or more Archive Warnings, but the author has chosen not to specify which ones. Only open CNTW works if you're comfortable with that uncertainty.
Characters and relationships
Tag the requested character(s) and/or relationship(s) that your gift focuses on. Minor or background characters and relationships should be placed in the Additional Tags.
Additional tags
Use Additional Tags for anything readers may want to know before opening the work, including kinks, potential squicks and triggers not covered by the Archive Warnings.
You can also list e.g., minor relationships ('Background Konor Guilliman/Tarasha Euten'), extra information about characters ('FtM Sigismund') or content ('Canon-Typical Violence'), genre ('Fluff', 'Angst', 'Omegaverse'), tropes ('Coming Out', 'Our Vampires Are Different'), etc.
Additional tags help people avoid content they are uncomfortable engaging with and find content they really, really want to engage with, so try to include tags that broadly cover the content and theme(s) of your fic.
Collection
Under Associations, the exchange collection should already be filled in automatically.
In Gift this work to, enter the username of your treat recipient.
If you have open assignments in the box for Does this fulfill a challenge assignment? (only visible if you do have open assignments), make sure none of them are ticked.
When you click Post, your work will be submitted to the collection and await moderator approval (which may take up to 48 hours, so please be patient).
😱 "Help! I posted my treat, but it disappeared!"
While the collection remains anonymous, your exchange works won't appear under the 'Works' tab in your dashboard sidebar menu.
To find treats you've posted, go to Works → Works in Collections.
💝 Have fun treating!
If you have any questions for the mod team—or for a recipient—please email:
I need a rules clarification- does "Any Character" encompass OCs as well as canon characters or is it a tag meant purely for canon characters only but any of those canon characters can be chosen?
Any Character can be any canon or original character. If it's one or the other, the tag will specify Canon or Original Character. 🙂
Check the email address associated with your AO3 account. If you haven't received an assignment email, please contact the mod team as soon as possible.
(And if there's any other issue with your assignment, also let us know!)
You can also access your assignment through the exchange collection page by clicking "My Assignment" in the sidebar.
📅 Assignment deadline
Assignments are due on Sunday, August 2, at 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT (deadline countdown).
Submitting your assignment: Important info and step-by-step guide 👇
📜 Quick rules recap
You have signed up to create a gift for your assigned recipient.
Your gift must be either:
A complete fanfiction of at least 500 words, or
A finished piece of fanart with at least clean line art on unlined paper.
You only need to create one gift featuring one character or relationship requested by your recipient, even if you matched on multiple requests.
You may choose any requested character or relationship from your recipient's sign-up, even if it is not one of the characters or relationships you originally offered.
Requests, mediums, ratings, and DNWs
Please read your assignment carefully.
Your gift must:
Focus on a character or relationship requested by your recipient.
Be created in the requested medium (fanfiction or fanart).
Comply with the rating requested by your recipient: General Audiences (G) or Teen And Up Audiences (T) for SFW requests; Mature (M) or Explicit (E) for NSFW requests.
Not contain content listed in that request's Do Not Wants (DNWs).
Note: Different requests may have different mediums, ratings, and DNWs.
We know it's always possible to rules-lawyer a loophole in your recipient's DNWs, but remember that your goal is to create a gift your recipient will enjoy. If your recipient's DNWs don't match up exactly with your preferences, consider this an opportunity to stretch your creative muscles. 😊
Apart from character/relationship, medium, rating, and DNWs, everything else in the request is optional. Prompts, likes, and other details are suggestions rather than requirements — but consider them a helpful guide to creating an awesome gift your recipient will love!
Questions for your recipient?
If you need clarification while working on your assignment, e-mail your questions to:
We'll pass them on anonymously. This helps preserve the mystery during the anonymous period and lets your recipient keep guessing right up until reveals.
📤 Submitting your assignment
Once your gift for your recipient is complete, upload it to the exchange collection:
On the collection page, click "My Assignment" in the sidebar. This will take you to a page showing your recipient's requests.
In the upper-right corner, you'll see two buttons:
❌ Default
Choosing "Default" means you will drop your assignment.
If you believe you won't be able to complete your assignment before the deadline, please default as soon as possible. Early defaults give the mod team more time to find a replacement creator for your recipient.
Dropped assignments are called pinch hits and will be posted to this tumblr for volunteers to claim.
Remember: every participant who completes their assignment is guaranteed a gift. If a pinch hit remains unfilled, gift reveals will be delayed until a replacement gift is completed.
✅ Fulfill
Choosing "Fulfill" will lead you to a Post New Work page that is already set up with your recipient’s username and the WH40K Summer Fest collection.
From there, follow AO3's normal posting process. If necessary, see the AO3 tutorial for posting a work.
⚠️ Exchange-specific requirements
Ratings
Your work must use one of the following Archive Ratings:
General Audiences
Teen And Up Audiences
Mature
Explicit
Works marked "Not Rated" will not be approved.
Archive Warnings
Your work must use the appropriate Archive Warning:
Graphic Depictions of Violence
Major Character Death
Rape/Non-Con
Underage Sex
No Archive Warnings Apply
Choose Not To Use Archive Warnings
Important! Note the difference between the two non-specific Archive Warnings:
👉 No Archive Warnings Apply means the work contains none of the four major Archive Warnings. Other potentially sensitive content may still be present and should be tagged appropriately.
👉 Choose Not To Use Archive Warnings (CNTW) means the work may contain one or more Archive Warnings, but the author has chosen not to specify which ones. Only open CNTW works if you're comfortable with that uncertainty.
Characters and relationships
Tag the requested character(s) and/or relationship(s) that your gift focuses on. Minor or background characters and relationships should be placed in the Additional Tags.
Additional tags
Use Additional Tags for anything readers may want to know before opening the work, including kinks, potential squicks and triggers not covered by the Archive Warnings.
You can also list e.g., minor relationships ('Background Konor Guilliman/Tarasha Euten'), extra information about characters ('FtM Sigismund') or content ('Canon-Typical Violence'), genre ('Fluff', 'Angst', 'Omegaverse'), tropes ('Coming Out', 'Our Vampires Are Different'), etc.
Additional tags help people avoid content they are uncomfortable engaging with and find content they really, really want to engage with, so try to include tags that broadly cover the content and theme(s) of your fic.
Collection
Make sure the exchange/recipient is tagged/added under both 'Open Assignments' and 'Post to Collections/Challenges'. These should be auto-filled; if not, add them manually.
Leave 'Gift this work to' empty (this is for posting treats, which will be explained at a later date).
Once you click Post, your work will be submitted to the exchange and await moderator approval (which may take up to 48 hours, so please be patient).
🤔 "I submitted my assignment. Now what?"
Once your work has been approved by the mod team and added to the exchange collection, its status on the "Assignment" page on your personal dashboard will change to "Complete!"
You can then have a drink and relax by the pool until the gifts are revealed — or browse other requests if you feel inspired to give someone an extra treat!
😱 "Help! I posted my gift, but it disappeared!"
While the collection remains anonymous, your exchange works won't appear under the 'Works' tab in your dashboard sidebar menu.
To find an exchange gift:
Go to Assignments in your dashboard.
To find treats you've posted:
Go to Works → Works in Collections.
💝 Have fun creating!
Please follow or regularly check this Tumblr for announcements and updates throughout the writing period.
Any pinch hits that need volunteers will also be posted here.
Questions for the mod team or for your recipient? Email us at:
Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
✓ Live Streaming✓ Interactive Chat✓ Private Shows✓ HD Quality✓ Free Actions
Free to watch • No registration required • HD streaming
Please be patient while we complete a final review of all sign-ups and run the matching process.
👉 Keep an eye on the email address associated with your AO3 account, including your spam folder. If the mod team encounters any issues with your sign-up, we will contact you there.
"What happens if I can't be matched?"
👉 If your requests don't match another participant's offers, your requests will be posted to Tumblr as an Initial Pinch Hit (IPH) for volunteers to claim. As long as you complete your own assignment, you are guaranteed to receive a gift.
👉 If your offers don't match another participant's requests, the mod team will email you and ask you to add additional offers within 24 hours of the sign-up deadline. If you do not respond, your sign-up will be removed from the exchange.
Assignments will be sent out as soon as matching is complete.
WH40K Summer Fest Exchange: Sign-up closes in 6 hours
Masterpost | Ask | AO3 & Rules | 2026 Tag Set | AO3 Automagic App
The sign-up deadline is Sunday, June 14, at 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT (countdown) – that's just 6 hours from now!
🤩 "When will I get my assignment?"
Once sign-up closes, the mods will do a final review of the requests before running AO3's matching algorithm.
As long as everyone has completed their requests correctly, filled out their Do Not Wants, and offered at least one character/pairing in a medium and rating requested by another participant, assignments will be sent out on Sunday.
If any issues are discovered during the final review, we may need a little extra time to contact affected participants and resolve them before matching can be completed.
Trust us, we're as excited to get your assignment sent as you are!
WH40K Summer Fest Exchange: Sign-up closes in 24 hours
Masterpost | Ask | AO3 & Rules | 2026 Tag Set | AO3 Automagic App
The sign-up deadline is Sunday, June 14, at 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT (countdown) – that's 24 hours from now!
If you've already signed up, now is a great time to:
Fill in any missing DoNot Wants and optional details in your requests.
Check the Sign-up Summary to make sure at least one of your requests and one of your offers match another participant's.
Browse other participants' requests on AO3 or on the AO3 Automagic App in case you're inspired to add more requests or offers of your own.
😩 "Oh no! My arch-nemesis has signed up! The Horus to my Sanguinius! The Rawne to my Gaunt! The consequences of an undeserved reputation for heroism to my Ciaphas Cain!"
If there is another participant whom you absolutely cannot be matched with, please email us a Do Not Match request at [email protected] !!! before the sign-up deadline !!!
Please include:
Your AO3 username
The AO3 username of the participant you do not wish to be matched with
Whether you want to avoid being assigned as their creator, their recipient, or both
You do not need to explain the reason for your request. We just need enough information to make sure you're not matched together and to avoid any immediate defaults. 🙏
WH40K Summer Fest Exchange: Sign-up closes in 48 hours
Masterpost | Ask | AO3 & Rules | 2026 Tag Set | AO3 Automagic App
The sign-up deadline is Sunday, June 14, at 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT (countdown) – that's just 48 hours from now!
If you've already signed up, now is a great time to:
Fill in any missing Do Not Wants and optional details in your requests.
Check the Sign-up Summary to make sure at least one of your requests and one of your offers match another participant's.
Browse other participants' requests on AO3 or on the AO3 Automagic App in case you're inspired to add more requests or offers of your own.
🤔 "What happens if my offers don't match anyone else's requests?"
If your sign-up is unmatchable because you haven't offered a character/pairing in a medium and rating that another participant has requested, the mods will contact you by email. You'll have until 24 hours after the sign-up deadline to update your offers.
If you do not update your sign-up by then, it will be deleted and you will not be eligible to participate in the exchange.
Because participants can add or remove requests right up until sign-ups close, we strongly recommend making sure your offers match at least a few other participants.
🤔 "What happens if my requests don't match another person's offers?"
If no one has offered to create a work for a character/pairing in a medium and rating you've requested, or if the AO3 matching algorithm cannot create a complete set of matches, your request will become an Initial Pinch Hit (IPH).
Pinch hits are unclaimed requests that will be posted to this tumblr for volunteers to claim.
As long as you complete and submit a gift for your assigned recipient, you will also receive a gift yourself, so don't worry if your request becomes a pinch hit. We have many eager volunteers, and the collection will not be revealed until everyone who is eligible has received a gift.
Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
✓ Live Streaming✓ Interactive Chat✓ Private Shows✓ HD Quality✓ Free Actions
Free to watch • No registration required • HD streaming
Just a heads up, looks like there’s a duplicate tag of “Orikan/Trazyn/Vishani”
Thank you for letting us know!
Fortunately, it seems the participants who have requested this pairing have all used Orikan/Trazyn/Vishani (Warhammer 40.000), so I have removed the other version of the tag.
WH40K Summer Fest Exchange: Sign-up closes in 1 week
We're halfway through the sign-up period and already have 41 sign-ups! 👏
If you're thinking about signing up – or if you've already done so – here are a few useful tips:
In an exchange, you'll be matched with another participant based on your requested and offered characters/pairings, media, and ratings. Unlike prompt memes or kinkmemes, where creators can choose specific prompts to fill, the exchange matching algorithm does not take your optional details into account.
Therefore, rather than requesting a single, highly specific plot, it's a great idea to offer a few variations of tropes (e.g., only one bed, fake dating, hurt/comfort), settings (do you prefer canon-compliant settings or are you open to AUs?), and relationship dynamics (soft and domestic? pining and angsty? enemies to lovers?). This gives your assigned creator a better sense of what you enjoy while still leaving room for inspiration and creativity.
The Sign-Up Summary is a list of all characters/pairings that participants have requested and offered.
Remember that you must offer at least one character/pairing in a medium and rating requested by someone else. Checking the Sign-Up Summary regularly is a good way to make sure your offers remain matchable.
The AO3 Automagic App lets you search requests by characters/pairings. You can also search for requests by usernames or keywords in the prompt, making it much easier to explore the sign-ups and find potential matches.
And don't forget the overview of nominated characters and pairings by @psi-scribe, if you're looking for inspiration or would like to add additional requests before sign-ups close.
The sign-up deadline is Sunday, June 14, at 3:59pm GMT | 5:59pm CEST | 11:59am EDT | 8:59am PDT (countdown).
The WH40K Summer Fest Exchange @wh40ksummerfest - Tumblr Blog | Tumlook
