Shopping · Community report
Find the books missing from a series
In a post on X, a Muse user describes setting it to search Facebook Marketplace, eBay, Amazon, halfpricebooks and other sources several times a day for the Horus Heresy books they do not have yet. Nothing found or bought is mentioned, so this page keeps every purchase with you.
What you can get
What it is
Listing alerts
A running list of listings for the titles you are missing, each with edition, condition, total price and a link, and nothing bought without you.
It came back right when
- Each result is a title not already on your owned list.
- The price shown includes shipping, or says that it does not.
- Each result links to a live listing.
- No purchase, bid or seller message was made without you.
The checks are editorial, not from the source.
- Record what you ownStops for your approval
Full series list, editions and a price ceiling.
- Run the searches
Named sites at the frequency you set.
- Send new matches
Title, seller, condition, total price and link; repeats skipped.
- Buy and updateStops for your approval
You buy or message the seller, then update the owned list.
Editorial, not from the source
Works when
- You collect a long series and have gaps that are out of print or hard to find.
- You know which editions you want and your price ceiling.
- You are happy to buy or message sellers yourself.
Does not work when
- You need a title quickly for a specific date.
- You want it to bid or buy the moment a listing appears.
- The items are rare enough to need authentication or grading that a listing cannot show.
Find the books missing from a series: review template
| Item | What it is based on | Status |
|---|---|---|
| [Missing title] | [Your owned list, with series number] | [Still missing or found] |
| [Listing] | [Seller's own description and photos, with link] | [New or repeat] |
| [Price with shipping] | [Listing total, compared with your ceiling] | [Under or over] |
The source case
On X, @KingRomstar says they set Muse up to search for the Horus Heresy titles they do not have yet, scanning Facebook Marketplace, eBay, Amazon, halfpricebooks and a few other sources several times a day. The post, a reply to @alexandr_wang, describes the search running; it does not say what was found, bought or at what price, or how matches were judged. It was checked on 2026-09-24 and is an individual report, not evidence that a given title is available or at what price.
A public report by someone outside this library. Not independently reproduced here.
From the source
Source excerpt
I've setup muse to search for horus heresy books that I currently don't have. It scans Facebook marketplace, eBay, Amazon, halfpricebooks, and a few other sources several times a day.
Quoted from the original posts. Not written by this guide, and not a result produced here.
Suggested prompt
Bring The series list and what you own, Edition, format or condition preferences, Maximum price including shipping, Sites to check and how often. Acts Searches the sites you name on the schedule you set. Sends you matching listings with links. Does not buy, bid, make offers or contact sellers without your approval. Source community report, checked 2026-09-24.
Written by this guide as a starting point, not quoted from the source. Your edits stay in this browser.
Other ways to ask
Editorial rewrites of the brief above, for a different emphasis. Copy them separately.
What you need
Editorial, not from the source
You supply
- The series list and what you own
- Edition, format or condition preferences
- Maximum price including shipping
- Sites to check and how often
Connected
- Access to the marketplaces you name, where a login is needed to see listings
Approved by you
- No authority to buy or bid
- Your approval before any seller is contacted
How to try it
Editorial, not from the source
- Write out the full series list and mark what you own, with the edition or format where that matters to you.
- Name the sites to check and any to leave out, and how often to look.
- Set what counts as a match: edition, condition, a maximum price including shipping, and whether marketplace listings must be local pickup.
- Ask for each find to come with the title, seller, condition, total price and a link, and for repeat listings to be skipped.
- Buy or message the seller yourself, then update your owned list so the search stops looking for that title.
Start from the list you own
A search for missing titles is only as good as its record of what is already on your shelf. Write out the whole series in order, mark what you own, and note the edition where it matters: a collector who wants matching hardbacks does not want to hear about a paperback omnibus. Long series are hard on searches because listing titles are inconsistent. The same volume can appear under its own name, a series number, a reissue title or a bundle description, and a listing of five volumes may hide the one you need. Give the agent the series numbers as well as the names, and ask it to open bundle listings rather than skip them. Then say what you will pay, including shipping, so every result can be judged against a ceiling.
Several sites, several times a day
The report this page is built on describes a search across Facebook Marketplace, eBay, Amazon, halfpricebooks and a few other sources, run several times a day. That spread matters because each site behaves differently. Marketplace listings are local, cheap and gone fast. Auction sites have end times. Large retailers mostly list new stock or third-party sellers at fixed prices, and used bookstores list what they have on the shelf. Checking often catches the short-lived listings, but only if repeats are filtered out; otherwise the same eBay listing arrives every few hours until you stop reading. Ask for each result to be compared with what has already been sent, and for new ones only. The post does not say what the search turned up.
You buy, it finds
Keep the purchase with you. A listing can look right and turn out to be a different printing, a book club edition, or a copy with damage the photos do not show, and some of that only comes out by asking the seller. On marketplaces, messaging a seller also shares something of who you are, and arranging a pickup is a decision about where you meet a stranger. So the task stops at the alert: title, seller, condition, total price and a link. When you do buy, update the owned list straight away, or the search will keep sending you listings for a volume that is already in the post. A collection completed this way is slower than bidding automatically, and far less likely to end with two copies.
Open Muse to try it. That is the product's own site; this guide is not part of it.
Limits and confirmation points
Limits to confirm
- One attributed report. It describes the search running, not what it found or how often a listing was a real match.
- Listing titles for a long series are often inconsistent: omnibus editions, reprints and different covers can look like the volume you need or hide it.
- Marketplace listings can go quickly and are not always accurate about condition. A match is a lead, not a purchase.
- Nothing here authorizes buying, bidding, making an offer, paying, or messaging a seller on your behalf.
Stop and check
Editorial, not from the source
- Before it starts: confirm the owned list, the editions you want and the price ceiling.
- When a listing appears: you decide whether to pursue it.
- After a purchase: update the owned list so the search moves on.
If it goes wrong
Editorial, not from the source
- Results include titles you already own
- Check the owned list for spelling and edition differences, and ask for matches by series number as well as title.
- The same listing keeps coming back
- Ask for results to be compared with earlier ones so only new listings are sent.
- A listing's condition or edition is unclear
- Ask for the listing's own description and photos to be quoted rather than summarized, and put any question to the seller yourself.
Common questions
Can Muse find the books I'm missing?
One collector reports setting it to search Facebook Marketplace, eBay, Amazon, halfpricebooks and other sources several times a day for the Horus Heresy titles they don't own. The post does not say what it found. This directory has not reproduced it.
Which sites can it check?
The report names Facebook Marketplace, eBay, Amazon and halfpricebooks. Name the ones you want, and note any that need a login to show listings.
Will it buy a copy when it finds one?
Not as described here. It sends listings with links; buying, bidding and messaging sellers stay with you.
How do I stop it sending titles I already have?
Keep the owned list current, include series numbers and editions, and update it after each purchase.
How often should it search?
The report says several times a day. That suits fast-moving marketplace listings; for slower sellers, once a day may be enough.
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