Table of Contents[Hide][Show]
Your final goal in Blue Prince is to reach Room 46 — and it’s an extremely tough goal. If you manage to make it to the Antechamber at the top of the map, you’ll find a Basement Key and another locked door. The north door of the Antechamber leads to Room 46 and there’s only one lever that opens that door. You’ll need to reach the Underground. If you prepare properly, the Underground path to the Room 46 Lever can be permanently unlocked so there’s never any randomness.
Getting to the Underground Lever isn’t too difficult once you have the Basement Key — but returning to the house and reaching the Antechamber with enough steps to reach it? That’s tricky. Here’s how to find the fourth lever and open Room 46.
For more information on unlocking the other three doors in the Antechamber, follow our guide here.
Where Is Room 46?
The mythical Room 46 is your final goal in Blue Prince. It is found at the very end of the path and always appears in the same place — through the north door in the Antechamber.
- Room 46 is found through the north door of the white Antechamber found at the top-center of the house map.
- Entering the Antechamber rewards you with the Basement Key — which accesses two locked doors to the Underground.
- The lever that opens Room 46 is only found in the Underground.
Once a Basement Key door is unlocked, it is unlocked permanently — so you’ll want to use it on both locations before throwing it away.
Where To Use The Basement Key
The Basement Key is an item found in the Antechamber and will be lost if your run ends. We highly recommend placing a Coat Check to store the Basement Key if you can’t use it. The key unlocks two doors permanently outside the house.
- Basement Key Door #1: Found on the lower level of the Foundation. The Foundation is a permanent room that always appears in the same place after drafting it once. To unlock the lift in this room, reach the side with no doors from the exterior of the room — essentially, connect a room with a door facing the Foundation wall that has no doors.
- This reveals a hidden lever on the backside. Activate the lever to permanently unlock the lift. The lift takes you down to the Underground with a Basement Key. In the Basement area, solve the moving carts puzzle to reach the button on the nearby wall, only accessible by walking on the wall of stuff.
The first Basement Key is the easiest to find and you’ll naturally place the Foundation while progressing. The second one requires some preparation.
- Basement Key Door #2: The second door is found at the bottom of the drained Fountain just outside the house entrance. To drain the Fountain, you must place a Pool room and temporarily unlock the Pump, Lockers and Sauna rooms. Place the Pump room and solve the puzzle inside to drain the Fountain completely.
Once you’ve reaching the Pump Room, everything you need to solve the puzzle should be available to you in that room, you’ll have enough space in the reserve water tanks to pump all the water out of the fountain.
The Well entrance reaches the opposite side of the Reservoir — and gives you the same access as the Tomb.
Additional Underground Entrances
To reach Room 46, you’ll need to reach the Underground Lever. There are multiple entrances to the Underground, but to solve the puzzle, you’ll need to reach the opposite side of the mine cart and move it to access all parts of the cog wheel room.
- Tomb: Draft the Tomb at the West Gate Outer Room and flip the arm statue switches in the correct order to unlock the path to the Crypt.
- Solution: The order is: 1 Hoe (Gardener), 2 Bread Shovel (Chef), 3 Pitchfork (Farmer), 4 Chimney Brush (Chimney Sweep), 5 Broom (Maid), 6 Riding Crop (Horse Rider), 7 Mitre / Mace (Crown)
- In the Crypt, interact with the Scythe statue to open the door to the Underground.
The Tomb entrance leads to the same area as the Fountain entrance. This is where you can move the mine cart or go to the Cog Wheel Room and change the orientation of the bridge to reach the Underground Lever. We’ll talk more about that below.
- Grounds: Combine the Broken Lever, Sledgehammer and Power Pack at any Workshop room to create the Power Hammer. This special item smashes through weak walls.
- Use it on the grounds at the blocked-up doorway across from the Grounds stone balcony. This leads to the same basement as the Foundation Basement Door.
The Power Hammer leads to a useful secondary entrance that is always open once unlocked. The last path we’ve found is through the Precipice.
- Precipice: To unlock the Shortcut Door to the Underground in the Precipice, reach the circular room with unlit candles.
- Combine the Magnifying Glass and Metal Detector at any Workshop to create the Burning Glass. Use it on the candles to lower stairs and unlock a side entrance to the Underground.
If you haven’t opened the path to the Precipice, follow our guide here to find all four gas valves.
How To Reach Underground Lever
The Underground Lever is the final lever that unlocks Room 46 in the Antechamber. You’ll need to unlock at least two of the Underground entrances to access the Underground Lever. Here’s what to do.
- Access the Underground through the Fountain Basement Door, the Precipice Shortcut or the Tomb Secret Path to reach the inner Underground Reservoir.
- Go toward the Minecart blocking the way. No matter what, the Minecart bifurcates the Underground. If you move it back toward the Tomb door, you will open full access to th Cog Wheel Room from the Basement / Foundation Door.
Circle back around and enter the Underground through the Basement / Foundation and reach the Cog Wheel Room.
- From here, use the device to turn the cog wheel so you can access the room at the 8 O’clock position on the Cog Wheel — you’re at 6 O’clock from the Reservoir Entrance.
- In this hidden room, unlock the shortcut door then backtrack to the bridge control and turn it so you can access the 12 O’clock from this shortcut door room.
Once the bridge is in position, you can easily return from any Underground entrance. Follow the path through the Cog Wheel Room to the Underpass road. The Underpass leads to the Inner Sanctum where you’ll find the Underground Lever.
- Using the Inner Sanctum lever will unlock Room 46 in the Antechamber.
From this point on, getting to the Inner Sanctum and turning the Room 46 lever can be done at any time, even before you begin your run through the estate. The tricky part isn’t activating the lever — it’s reaching the end. You’ll need to waste 10+ steps to go down into the Underground, use the Lever, then leave.
There’s a mysterious red door in the Underpass — we’ll talk about how to unlock that later. Just know that the red door does NOT make runs easier and is only used to find more permanent upgrades.
