Dowsing Rod
Spoilers Ahead
This page contains spoilers for the Workshop. View at your own discretion.
The Dowsing Rod is a special item in Blue Prince. When drafting a room, the Dowsing Rod appears by one of the drawn floorplans, which can be chosen for additional luck. It also still acts like a Compass.
How to obtain
As a contraption, the Dowsing Rod can only be obtained in the Workshop by combining the Compass and the Shovel.
Usage
The effects of the Compass are inherited; see Compass#Usage for details. Unlike the normal Compass (and the item's main usage), this effect applies even if the item is currently in the Coat Check, or if it was obtained earlier in the day then lost entirely (such as via 
[Outer Room: Trading Post]).
When drawing floorplans, the Dowsing Rod's model appears at the bottom of the drafting interface, first pointing in two random directions before settling on one of the three floorplans. Choosing and drafting that floorplan after this point triggers the Dowsing Rod's effect, boosting the drafted room's luck and giving it a significantly higher chance to contain items.
- If floorplans are redrawn, the Dowsing Rod will reselect one of the new floorplans. The Dowsing Rod's animation after redrawing is slightly faster, as the Dowsing Rod only points in one random direction before deciding.
- In many cases, the Dowsing Rod's effect does not stack with other luck bonuses, instead using its own system entirely.
- If luck is extremely high from other sources, it is possible for more items to be obtained from those other sources than the Dowsing Rod's effect, making it potentially preferable to avoid the chosen floorplan. However, the level of luck required for this to be the case is almost never reached in regular play.
- The Dowsing Rod doesn't choose a floorplan until after it finished making its initial random movements. Choosing a floorplan "prematurely" with the Dowsing Rod can have unexpected consequences.
- If the Dowsing Rod chooses a floorplan but that floorplan isn't drafted, the slot seems to remain affected by the Dowsing Rod until it makes its next choice. Initiating a new draft and quickly choosing the floorplan in that slot appears to cause it to benefit from the Dowsing Rod's effect, even while the Dowsing Rod is still in motion.
- Even when drafting prematurely every time, it is still possible to occasionally benefit from the Dowsing Rod's effect. The Dowsing Rod seems to be able to pick a floorplan slot even after drafting finishes if a floorplan is drafted prematurely, allowing that slot to benefit from the Dowsing Rod's effect on the next draft if it is also drafted before the Dowsing Rod makes its next choice.
Some rooms are almost never selected by the Dowsing Rod. These are typically rooms that never spawn additional items, even at extremely high luck.
Beyond the Estate
This section contains datamined information about ALL rooms that the Dowsing Rod avoids. It may contain spoilers for various stages of the game.
The Foundation, Rotunda, Room 8, Closet, Walk-in Closet, Attic, Pantry, Chamber of Mirrors, Coat Check, Freezer, Passageway, Locksmith, Showroom, Bookshop, The Armory, Mount Holly Gift Shop, Maid's Chamber, Darkroom, Vestibule, Casino, Mechanarium, Treasure Trove, Lost & Found, Toolshed, Shelter, Shrine
In the case that all three offered rooms are one of the rooms on this list, the Dowsing Rod will still pick one of them; in all other cases it picks a different room.
Beyond the Estate
This section contains datamined information about exact impacts on luck. It may contain spoilers for various stages of the game.
This section references details from normal luck, as it is an extension of that. See Luck#Details for info.
The Dowsing Rod has its own Dowsing Penalty, which starts at 0 and can increase from effects below. It does not impact anything outside this effect.
When the Dowsing Rod is used on a room, a +32 Luck bonus is applied and the standard Luck Penalty does not apply. Then:
- 0-2 Dowsing Penalty:
- If the room is any of Spare Room, Gallery, Garage, Music Room, Trophy Room, Ballroom, Utility Closet, Boiler Room, Workshop, Hallway, West Wing Hall, East Wing Hall, Corridor, Secret Passage, Great Hall, Cloister, Commissary, it gives variable items.
- 18- Luck: Runs the regular non-Dowsing Rod routine. If it rolls 0 items, it gets increased to 1 item.
- The only way to trigger this is having 4 Maid's Chambers drafted.
- Otherwise: 81.6% for 1 item; 3.4% for variable items; 10% for 3 items, +2 Luck Penalty, +1 Dowsing Penalty; 5% for 4 items, +3 Luck Penalty, +2 Dowsing Penalty.
- 3-5 Dowsing Penalty:
- 48% for 1 item; 32% for variable items; 20% to run like it was 0-2 Dowsing Penalty.
- 6+ Dowsing Penalty:
- 48% for 1 item; 52% for variable items.
In almost all cases (without 4 Maid's Chambers), "variable items" means 5% for 3 items and +3 to Luck Penalty; 95% for 2 items and +1 to Luck Penalty.
Note that, since the Dowsing Rod still increases the normal Luck Penalty when used, once it has been used enough, normal drafts without the Dowsing Rod effect are more likely to act like a Maid's Chamber has been drafted.
Interactions
- The Dowsing Rod may be stored in Coat Check or retained with the Moon Pendant like any other special item. Starting the day with the Dowsing Rod in Coat Check, or with it already in the inventory due to the Moon Pendant, will cause the Compass to be unobtainable today. The Shovel is unaffected and can be obtained like usual.
- [Outer Room: Shelter] Drafting a Lavatory or Furnace under the Dowsing Rod's effect additionally treats that room as though it had been sheltered. This does not apply to any other rooms.