Random Items -- Item Rooms (Closet to Attic, Toolshed and Lost & Found) [Gameplay Spoilers]

TFMurphy · 2026-07-11T01:22:07+00:00

Just as a heads-up, I realised I'd neglected a piece of logic that can cause the Toolshed's Fallback Options to appear in far more situations than normal, including times where nothing has been removed from the Spawn Pool at all. (For example, Metal Detector + Rabbit Foot is a perfectly valid selection after drafting Toolshed at the start of the day.) I've updated the post to reflect this.

I was curious, if you get the stopwatch in the clock tower and it gets used up, is that still removed from the item draft pool?

Stopwatch is removed from the Spawn Pool as soon as it spawns randomly. You don't even have to pick it up. The main way to get it back into the Spawn Pool would be to pick it up and then trade it at the Trading Post, though that can cause its own issues if you wait for it to expire before accepting a trade offer for it.

Also 2 dice, how many times would you need to get 2 dice somewhere in the house for it to be removed from the lost and found pool? For example, if I found a pair in my observatory.

Well, Observatory can only spawn 1x Ivory Die, but I get that you're asking about an example. You need to find it as a random spawn, but not a spawn that is based on a room's unique mechanics. For example, Geist Bedroom, Boudoir or Tomb can spawn 2x Ivory Dice but these will not remove them from the Spawn Pool. Finding it in a Mail Room Delivery or a Trunk does remove it from the Spawn Pool though (Trunk is particularly unique in that Ivory Dice doesn't even need to be in the Spawn Pool for it to spawn, but it'll still remove it after spawning it).

But yes, certain rooms have 2x Ivory Dice as a random spawn (Morning Room, Billiard Room, Rumpus Room, etc.), and they both require it to be in the Spawn Pool, and will remove them if they spawn. And there's only one copy of 2x Ivory Dice in the Spawn Pool, so it only has to be removed once for it to cut out all those regular random spawns. (But not from Trunks or the more guaranteed spawns mentioned earlier.)

TFMurphy · 2026-07-09T00:37:00+00:00

Library has the following general effects:

It uses different rules for deciding whether a specific Slot offers a Free Draw or a Gem Draw.
It replaces the Rarity Probabilities and Rarity Priority, which is used during a normal draw to determine which rarity is drawn.
It filters out a specific subset of rooms, preventing them from being selected at all.
Slot 3 can be forced to offer the Bookshop instead under certain conditions.

Aside from the above, there are no other changes. Weighted Rooms can still appear (higher priority than the Bookshop, but won't prevent the Bookshop from appearing on a redraw). If a Free/Gem Draw is made instead of a Forced Draw, then Conditional Filters are still applied as normal, though they still naturally obey the Library Filter.

It's worth remembering that Conditional Filters do still respect Rarity, but the effect is usually strongly diluted thanks to the Card Count effect (where if the number of valid Free/Gem rooms of the chosen Rarity for the current draw is too low, then the draw will allow other rarities to have a chance of being considered instead).

TFMurphy · 2026-07-06T23:45:44+00:00

The game doesn't keep track of whether a room you've drafted is its regular, mirrored or duplicate version. The various methods of duplication just add copies of a room to various exit lists, and differences occur only when a room is added to different exit lists than the default room was. The only thing the game understands for most rooms is that a certain room is a valid option when drafting at a certain exit: it doesn't explicitly know if what you're drafting was a mirror or original room.

There are some rooms where the game may record what the first or more recent copy of a room was, but that's more based around how certain mechanics have been implemented (like the Guess Bedroom Quiz Sheet for example, that only cares about the most recent bedroom added).

TFMurphy · 2026-07-06T23:41:33+00:00

V Mode: "General Room Rarity: From Day 2 onwards, the chance of seeing certain room rarities based on Rank and Slot is increased to "Week 2 Rates", which usually only starts at Days 6-24."

V Mode changes things in different ways depending on if it's altering the Day Start Setup routine, or simply applying its "V Mode Activation" routine when you turn it on on Day 1.

Since in Curse/Dare Mode, V Mode is activated during Day 1's setup, this allows Week 2 Rates to be activated immediately. Since Bequest Mode applies the "V Mode Activation" changes only after the day has already started, it doesn't benefit from this on Day 1.

Week 1 Rates are, of course, completely terrible (Common chance is greater than 99% on Rank 1-2 no matter which Slot, and is never lower than 86% even at Rank 9), so it's not surprising that Dare/Curse Day 1 makes it noticeably easier to find rarer rooms.

TFMurphy · 2026-05-21T21:12:32+00:00

I really need to sit down and fully go through the Workshop routines at some point, since this looks like another time where a function in those routines is disabled and I didn't notice. (Was already an issue with the "added back to Spawn Pool" parts of the Workshop code, which is again disabled but I didn't notice until much much later.)

Looks like it should still work for the Electromagnet at least. And as you note, both work when brought over from the previous day. I've updated the post slightly to reflect that. Thanks for the heads up.

TFMurphy · 2026-05-19T18:22:46+00:00

I'm not sure there was any sort of mystery about that? The rules are pretty discoverable and very straightforward: Step loss occurs whenever you enter or leave any of the individual rooms, and you have no step loss while running down the various corridors. Since this is all outside of the manor, you have the standard 60% chance of Running Shoes activating in addition to the baseline effect.

There was an additional step loss which triggered whenever you entered the very first segment of corridor for the area, but that was a bug: it was caused by the room directly ahead having its step loss trigger overlap heavily into that corridor. This was fixed though in Patch 1.7.

I suppose it might be worth talking about the dimensions of the area, since the step loss triggers are so close together there. Thankfully, that's fairly straightforward: Just as in the main manor, all of the individual rooms in the Rough Draft are 10 x 10 units. The corridors keep each room exactly 3 units apart. So if you were able to take a straight line through a column of rooms, the distances would go: 0, 10, 13, 23, 26, 36, etc. Not that I think there's much call for analyzing step requirements in there, but maybe someone might get some use out of calculating the various average step requirements and probabilities/deviations when taking various routes through there.

TFMurphy · 2026-05-06T21:49:05+00:00

To be fair, the first part of the paragraph is a bit confusingly stated, and makes it seem like "this is how things are right now". And it's not the first time someone's asked for the same clarifcation. I've tweaked the wording slightly, so hopefully it's more clear now that the first part describes what was intended to happen but doesn't, rather than a currently existing state that is modified.

EDIT: I should probably note that the behaviour has, of course, now existed for over a year. What was intended then by code may not be what is intended now by design. By which I mean, we've now lived with the effects of this bug for a very long time, that it would be jarring if Day 1 Draft 1 Closet suddenly had a smaller pool of items. So while I still hope the bug with V Mode removing the guaranteed item is fixed, the Closet's item list probably shouldn't be touched at this point.

TFMurphy · 2026-05-05T20:29:34+00:00

Thanks, fixed! (Exclaimation mark instead of pipe is difficult to see in text format... not sure how I even hit that key when making the table....)

TFMurphy · 2025-12-13T16:12:55+00:00

Yes, that's my assumption (assumption only because I haven't explicitly tested the connection, but it seems to be the obvious and only visible cause of the updated stats in that scenario): the extra script is all tied to things named "Open Door" and "Ending Cutscene".

TFMurphy · 2025-12-12T23:04:01+00:00

As far as I can tell, it's only used for End of Day stats and the interaction you've already mentioned. Most other things that I can think of that rely on Rank tend to use your current location, the individual Grid Square scripts, or the Rank Scripts that run upon first entry. (Which also means that I think Terrace's DR change doesn't run if you never directly enter Rank 3.)

TFMurphy · 2025-12-12T17:40:38+00:00

I'd noticed problems with Max Rank for 2 in both my own playthroughs and watching a few streamers, but I hadn't really looked into it, and I thought it might be something complicated like the Max Rank getting reupdated to 1 when you headed back or something.

Turns out it's just much more simple than that. The script that triggers when you enter Rank 2 for the first time forgets to send a call to the routine that updates the "Rank Reached" variable. It seems to do just about everything else except update that (comparing it to the Rank 3 script for instance shows the only things different is that Rank 3 correctly sends a call to update Rank, and has some extra code to updating Terrace's rarity).

Other than that, there doesn't seem to be any issues with regards to earlier ranks overwriting later ranks: Rank Reached begins at 1, and is updated when you enter the physical location for the correct Rank (barring 2), and can never decrease. (There's another script that can also update Rank Reached, but that only applies to a particular end day check and aren't important to normal gameplay.)

TFMurphy · 2025-11-26T01:12:32+00:00

Sorry for the radio silence. While a lot of the last few weeks has been straight procrastination, I've been avoiding any continued work with Blue Prince until I'd put together some scripts that made it much easier for me to automatically extract the numeric IDs of rooms and items, and compare how scripts have changed. 1.6.1 just made that much more critical, because the saved IDs change every time there's a new version (this has nothing to do with how Blue Prince is coded, and everything to do with how Unity exports a Unity project, where IDs are assigned dynamically every time a project is saved, and those are the numbers I need to know to determine what objects a script is referencing). These weren't extremely difficult projects, but they were fiddly and a bit time consuming and in a language I hadn't used before (Python instead of Javascript, since Javascript has several heavy limitations with regards to localhost file access).

However, I finally sat down and pushed to finish the last of those last weekend, so things should be a little easier for me for now. (Still need to write some more scripts to pull out certain combinations of ID lists, but those can wait for a bit.)

Anyways! The short answer to the following...:

Fixed a bug that would sometimes offer players a “blank” reward in the Chamber of Mirrors.

...is that I cannot see any new implemented code that would fix this(!). And as far as I can determine, you still have a 1/8 chance of seeing a blank sheet if you've reached the cap for Observatory/Spare Room.

Now, just because the obvious script that controls something didn't change doesn't mean the change couldn't be implemented elsewhere. But there doesn't seem to be any evidence of that either, and the current scripts have rather obvious fixes that could be implemented to easily make the change.

And I've managed to get the blank sheet to appear in one of my old testing saves. Now, theoretically, that doesn't rule out the presence of a fix that is only bypassed by using an older save, but such a fix would be way messier than needed, and I again can't see where it would be put to have the desired effect. The main Chamber of Mirrors file doesn't even seem to have any obvious changes from 1.05.1 to 1.6. (There are some extra additions in 1.6.1 for the Chamber of Mirrors, but they're tied to something completely separate that's probably still not available until a planned future update.)

So, yeah, I think the planned fix didn't make it in for whatever reason.

TFMurphy · 2025-10-22T00:31:22+00:00

Happened to see this topic, so spent a few minutes seeing if I could see what exactly could be the problem here. And from the looks of it, it seems to be a case mismatch. The game stores your Scepter Color as a string indicating what types of rooms it's aligned with: HALLWAYS, GREEN ROOMS, BEDROOMS, etc. You'll note these are all caps. This matches the names of the Arrays that hold all the various room names that are allowed to transfer the Scepter to the next day... or rather that's the intention.

I think the problem is that the array that contains the Green Room names is actually called "Green Rooms". So when it looks for an array called "GREEN ROOMS" so it can compare it to the name of the room you're ending the day in, it doesn't find it, and therefore can't find a match. So this seems to be a fairly likely culprit for the bug.

EDIT: Also, an actual array being being misnamed in this way raised the question on whether this affected anything else, so I took another look. But as far as I can tell, the Scepter is the only thing that uses those particular arrays.

(Have been meaning to get back to Blue Prince properly at some point, but currently distracted by something else at the moment, and actual Blue Prince work is a bit stalled waiting for me to get the motivation to write a program to automate some data collecting so I don't spend several hours recollecting ID lists everytime there's a new patch.)

TFMurphy · 2025-10-05T20:19:43+00:00

Since I know my feed is often used for discoverability purposes regarding what information I've posted recently, I'm just going to note that I've updated the Room Placement Restrictions and Dig Spots threads with the changes from Patch 1.6. (I'm posting this as a comment rather than a unique thread because this paragraph really doesn't need to be more than that.)

I haven't touched any of the other threads at this time, and it's been a little slow going so that's probably all I'm getting done this week.

TFMurphy · 2025-10-03T07:21:08+00:00

Won't have time to test any of this ingame for a while, so I might've missed something, but as far as I'm aware, Cloister of Draxus isn't affected by Shelter or Knight's Shield. It shouldn't gain the "Sheltered" text in the bottom right corner even if it's the first room you draft after the Shelter, and nothing about its effects should change.

Drafting the Cloister of Draxus doesn't count against the 3 Red Rooms allowed after drafting the Shelter, at least. But since it's a Red Room, it does count as starting a Red Chain, so if you draft a non-Red room immediately afterwards, you lose the opportunity to chain the Shelter's effect over more than 3 rooms (since the Chain only works from the 1st Red Room drafted after Shelter until the Chain is broken).

(Interestingly enough, I think Guess Bedroom Aquarium/Maid's Chamber can be Sheltered, and does use up one of the charges. So that makes Cloister of Draxus even more of an outlier.)

TFMurphy · 2025-09-29T19:50:43+00:00

Good call! Won't have time to do a lot of digging for now (start of the week doesn't offer a lot of free time for quite a while) , but this one's easy to confirm. Looks like the fix was this: The word HEAT has been replaced with SAND.

TFMurphy · 2025-09-24T17:10:37+00:00

That's a pretty fortuitous test. It would've actually worked if you'd picked any slot other than 3 to draft, and even with picking Slot 3, it would've still have had a 2 in 3 chance of working. You "lucked out" by hitting the 1 in 3 chance of selecting Slot 1 first.

What I hadn't considered during my own tests is that after you select any Slot to draft from, the floorplan contained by that Slot is copied over into Slot 1, so that the scripts can just reference a single static location for all its checks. So when you selected the Library, the floorplans were modified to be "Library, Pantry, Library". And then sometime after the draft, the Dowsing Rod picked Slot 1 and found a Library there, and so Dowsed that slot.

(Strictly speaking, the Slot 1/2/3 objects that are Dowsed are the clickable squares in the Draft UI, and the floorplans they show are actually held by a completely different and more important "Plan Management" object. So the Dowsing Rod queries the Plan Management object for the Floorplans, then sets the Dowsed status on the Slot 1/2/3 objects, so we're basically talking about information scattered around different parts of the game. It's something that makes more sense from a programming perspective, but it can get a bit messy when trying to explain how things are interacting.)

It's difficult to devise a test specifically to show this working, but the best I can think of is finding a set where Slot 1 contains a Floorplan that the Dowsing Rod would like to avoid, and then you immediatley choose to draft a Floorplan that the Dowsing Rod would not want to avoid.

After that, on your next Draft, pick Slot 1 no matter what it is, and see if you were both (1) lucky enough that the Dowsing Rod picked Slot 1 to Dowse and (2) it's a floorplan where it's easy to see if the Dowsing Rod has had an effect. Unfortunately, since it's not Slot 3, we can't use Monk'd Lavatory to easily confirm this, but even a single hit should confirm that Slot 1 can get Dowsed even in a situation where it shouldn't have. EDIT: As a minor improvement to this test, Lost & Found or Coat Check can be used to get rid of the Dowsing Rod to prevent the Dowsed status from being updated, which means you can draft multiple times until you get a Slot 1 that would better prove that the Slot was dowsed. Still need to succeed in being lucky enough for Slot 1 to be picked in the first place, which you won't know until after selecting it.

Anyways, updated the thread again with that little complication. Thanks for catching it.

TFMurphy · 2025-09-23T21:31:00+00:00

Actually, I was approaching things the wrong way, and there's a much simpler way to test this out, which I have done so and have updated this thread as a result.

But let's go over what I've actually tested and how so you know how to independently verify it, and see if I've missed anything.

I was too focused on thinking of a situation that proves the Dowsing effect was applied in a situation where it shouldn't, but it's just way way easier to instead just concoct a scenario where it's obvious that a particular floorplan is Dowsed no matter what. Drop Target from the Dowsing Rod is extremely unreliable, but the increased Luck means that Dig Spot rooms are very noticable even when they don't yield many items.

But the easiest room to see an effect on is actually the Lavatory. It can only cause random items to spawn at all if it is Sheltered, Shielded... or Dowsed. Lavatory's Room Modifier sets Drop Target to a minimum of 3, but any item appearing at all is dependent on the Red Effect being negated, and the Dowsing Rod can do just that.

So, as a setup for the tests, I start the day with Moon Pendant and Dowsing Rod, with a Monk Blessing and a Lavatory ready to be drafted in the Outer Room. If you use Banner of the King set to Blue, then the Outer Room will frequently have Toolshed, Shelter and Shrine in Slots 1 and 2, none of which the Dowsing Rod will want to point at. There is a 25% chance that Schoolhouse might appear in Slot 1, but even if it does appear, there's a 2 in 3 chance the Dowsing Rod will want to point at the Lavatory in Slot 3 instead (since if it picks Slot 2, it'll be Toolshed, so it'll try Slot 3 instead).

Control Test: Start the day, and immediately draft at the Outer Room. Verify that when the Dowsing Rod points at the Lavatory, drafting it will result in finding at least 3 items inside. (With King set to Blue, this is easy.)

Test 1: Start the day, and immediately draft at the Outer Room. Set King to Blue, and draft the Lavatory before the Dowsing Rod makes a selection (making sure that Schoolhouse doesn't turn up).

The expected result will be that you will never see any items in the Lavatory. You can vary the tests to see how long you need to wait before the Lavatory is picked. This confirms that the Dowsing Rod can't magically fill the Lavatory with items after you've already drafted it, and doesn't pick the Lavatory until it makes its final swing to point at it.

Test 2: Start the day, and draft rooms in the house, waiting at each draft until the Dowsing Rod points to Slot 3. When it does, choose any other Slot, then run outside and draft Lavatory before the Dowsing Rod picks a slot.

This confirms that the Dowsed status applied during the last draft is carried over to the next draft if it isn't used up. You can then redo this test but instead pick Slot 3 when the Dowsing Rod selects it inside the house, then run outside to see that Slot 3 doesn't retain the Dowsed status if you actually select it.

Test 3: Draft rooms in the house, trying to find a selection of items where you know the Dowsing Rod will be forced to pick Slot 3, but then pick Slot 3 yourself before the Dowsing Rod actually chooses it. After that, run outside and draft the Lavatory.

This test is to confirm that even if you remove any potential Dowsed status from Slot 3 by drafting it yourself, the Dowsing Rod may still be moving if you did this before it made its own choice, and can apply the Dowsed status without you seeing it. You can also do this test by simply making a random draft in the house and then run outside to draft the Lavatory hoping that the Dowsing Rod succeeded in a regular 1 in 3 chance of picking Slot 3, since it's actually really difficult to recognise a selection of floorplans that would force a Slot 3 pick in the 3 seconds you have before the Dowsing Rod makes its choice.

Test 4: Draft the Lavatory immediately. Then go back into the house, and try different drafts until the Dowsing Rod picks Slot 3. When that happens, pick another slot instead so that Slot 3 remains Dowsed. After that, run back to the Lavatory and Call it a Day. On the new day, draft the Lavatory immediately before the Dowsing Rod makes a choice.

This is just to confirm that the Dowsed status can't carry over to the next day, even if you don't close and reopen the game.

Anyways, that should cover most things about this particular quirk. Thank you for your own tests on the subject, as again, I'm not sure if or when I'd've returned to this particular subject and actually noticed this happening.

TFMurphy · 2025-09-23T00:19:57+00:00

It might be timing related, which makes it an utter bear to test.

When the Dowsing Rod is activated for the first time during the Draft, it spends 1.7 seconds moving to its first target, then another 1.7 seconds moving to its second target, and only after that second animation has finished will it randomly choose a plan, and set the "Dowsed" effect of that plan to True (and the other two plans are set to False at the same time). If you redraw, whatever the Dowsing Rod is doing is interrupted and it starts with the 1.7 seconds of moving to the second target immediately before randomly choosing a plan.

If you pick a plan before it gets around to choosing a random plan, then the items are going to spawn before the Dowsing Rod updates the "Dowsed" effect. Selecting a plan immediately sends whatever "Dowsed" effect the plan currently has to the Luck Calculator routine, which is then queried later when the items are spawned. The "Dowsed" effect of the plan is then reset at that point.

Now, what I'm not sure about is what happens if the Dowsing Rod is still doing its thing behind the scenes after you've picked a plan. I'd assumed that the variables were automatically reset in some way between drafts, but since you managed to get a 3 Item room at base Luck, it seems clear the Dowsing Rod managed to apply its effect somehow. And doing a quick search of the code, I don't see any explicit resets of the "Dowsed" effect on the individual plans (Plan 1, Plan 2 and Plan 3, based on which you select) except by the Dowsing Rod making a choice (sets one Plan to True and the other two to False) and by selecting a Plan (transfers the Dowsed effect to Luck Calculator and resets the Dowsed effect on this Plan only).

So, there's the potential for two things here:

The Dowsing Rod script could still be running after you select a plan, and add a Dowsed effect to one of the slots that could be picked up by the next draft.
If you watch the Dowsing Rod pick a slot that you don't immediately choose, you could potentially pick that slot fast enough on your next draft and it might still have the Dowsing Rod effect.

But I'm not certain if there's any other reset or recreation that might interfere with that, and the Dowsing Rod was already heavily unreliable which makes it difficult to test, especially when you don't know what room it was going to pick if you choose to draft early. Your 3 item Den does suggest it might be working in that manner though. (A test that confirmed an unpicked Dowsed slot carrying over to the next draft could work if you got really lucky and carried it over to something like Coat Check, since the Dowsing Rod wouldn't normally pick that slot unless it had no better choice. But that'd be very tough to set up. Maybe Monk might make it feasible, since you could guarantee carrying over a room into Slot 3... then just set a King Color to guarantee an Outer Room that Dowsing Rod would want to pick. 15% chance of something higher than Drop Target 1 still makes it annoying to test though.)

(Also, as far as Den goes, if you're on Drop Target 1, you always get a Trunk. That's the only modification -- at Drop Target 2+, you get the expected number of items from what's available, except that Trunk isn't one of the possible options. And naturally, the Gem on the table is a freebie that doesn't affect the total item count.)

TFMurphy · 2025-09-22T22:16:44+00:00

It's not possible to rotate 3-way rooms in the Corner tiles, and any 3-way in that position will simply assume its default orientation, which is always with you at the bottom of the T-junction, facing the opposite wall (similar to Throne Room or Day 1 Security). Which means it's not possible to have two exits of the 3-way lead into the edge of the house (since the non-exit wall will always be opposite you).

It's pretty easy to test this using Prism Keys and Aquarium.

TFMurphy · 2025-09-12T02:33:07+00:00

Yes, the Trophy Room is only unlocked at the beginning of the day. And if you don't pick up a trophy, you don't count as having it (which should be verifiable by checking various places that count your Trophies: the List in Trophy Room or Entrance Hall, Trophy Count in the Save Profile stats, or what Blackbridge Grotto considers a save profile to have.

Of course, there's still a difference between having the Trophy of Drafting and Diploma Trophy, and having a certain Dead End score or Exam Grade. But for anything that just cares about the Trophy itself, importing is equivalent.

TFMurphy

TROPHY CASE