How to Reach Room 46 in Blue Prince
Room 46 is your ultimate goal in Blue Prince – the mysterious room that holds the key to your inheritance at Mt. Holly Manor. This comprehensive guide walks you through every step: unlocking the Antechamber doors, obtaining the Basement Key, navigating the Underground, and finally reaching the elusive Room 46.
This guide contains major spoilers for Blue Prince's main objective. If you prefer to discover solutions yourself, proceed with caution. We recommend trying on your own first – the journey of discovery is part of the magic.
Overview: The Path to Room 46
Blue Prince has a simple premise: find Room 46 in a manor with only 45 rooms. But the execution is anything but simple. Room 46 is located behind the north door of the Antechamber, which sits at Rank 9 (the top) of your blueprint.
Here's the challenge: all four Antechamber doors are sealed by default. You must find specific levers hidden throughout the estate to unlock them. And even then, the north door – the one leading to Room 46 – can only be opened from the Underground.
The journey typically takes multiple in-game days (runs) to complete. Don't expect to reach Room 46 on your first attempt. Each run builds upon the previous one through permanent unlocks and accumulated knowledge.
| Door | Lever Location | Requirements |
|---|---|---|
| West Door | Secret Garden | Secret Garden Key + solve wind vane puzzle |
| East Door | Great Hall | 7 Keys (or Foyer room, or Lockpick) |
| South Door | Greenhouse | Broken Lever item |
| North Door | Inner Sanctum (Underground) | Basement Key + Underground access |
Step 1: Reach the Antechamber
The Antechamber is a fixed room that always appears at the center of Rank 9 on your blueprint. Unlike other rooms, you don't need to draft it – it's always there. Your task is to draft rooms that create a path from the Entrance Hall (Rank 1) all the way up to the Antechamber.
Don't rush directly toward the Antechamber early in a run. Gather resources (keys, gems, steps) from lower ranks first. The Antechamber doors are sealed anyway – you need to find a lever first.
Recommended Strategy
- Focus on rooms in the lower ranks (1-5) to accumulate keys, gems, and coins
- Draft rooms with multiple door connections to maintain flexibility
- Look for lever locations (Secret Garden, Great Hall, Greenhouse) as you explore
- Only build toward the Antechamber once you've found and activated a lever
Step 2: Unlock an Antechamber Door
You only need to unlock one door to enter the Antechamber. Here are your three main options (the north door requires the Underground, covered later):
The easiest and most reliable method. You need:
- Find the Secret Garden Key (green key with flower icon) – spawns randomly in rooms
- Draft a room on the far west or east column (column 1 or 5) with a locked door facing outward
- Use the Secret Garden Key on that door to create the Secret Garden
- Inside, find the fountain with wind vanes on top
- Turn both hand cranks until all arrows point west (toward the wall)
- A hidden alcove opens, revealing the lever – pull it!
Requires resources but is straightforward once drafted:
- Draft the Great Hall (appears in mid-to-upper ranks)
- The Great Hall has 7 locked doors – the lever is behind one of them
- Bring 7 Keys, or use a Lockpick, or draft the Foyer first (unlocks all hallway doors)
- The lever location changes each day – check the miniature model in Drafting Studio for hints
More RNG-dependent but viable:
- Draft the Greenhouse (rare Green room, appears on east side)
- The lever on the wall is broken – you need a Broken Lever item
- Broken Lever spawns randomly (often in Security, Spare Room, or Workshop)
- Attach the Broken Lever to repair the mechanism, then pull
Tip: Store the Broken Lever in a Coat Check room if you find it before the Greenhouse. Items stored there persist between days.
Step 3: Get the Basement Key
Once you've unlocked at least one door and drafted a path to the Antechamber, enter it. You'll find:
- A pedestal rises from the center with the Basement Key
- A note that reads: "To continue up, you must go down"
- The north door (to Room 46) is still sealed
Any door you unlock with the Basement Key remains permanently unlocked even after your run ends. This is crucial – it means you only need to do this once per door.
The Basement Key can unlock two doors:
- Foundation elevator door – at the bottom of the Foundation room's elevator
- Fountain entrance – at the bottom of the drained Fountain outside
If your run ends while holding the Basement Key, you lose it and must return to the Antechamber to get a new one. Store it in a Coat Check room if you're running low on steps.
Step 4: Navigate the Underground
The Underground is a maze-like area beneath Mt. Holly Manor. Your goal is to reach the Inner Sanctum, where the north lever is located.
Underground Entrances
| Entrance | How to Access | Notes |
|---|---|---|
| Foundation | Draft Foundation, activate elevator, use Basement Key | Most reliable entrance |
| Fountain | Drain Fountain via Pump Room, use Basement Key at bottom | Requires Pool + Pump Room puzzle |
| Tomb | Draft Tomb at West Gate, solve angel statue puzzle | RNG-dependent (may not appear) |
| Precipice | Light 4 outdoor flames, then torch room | Permanent entrance once opened |
| Cliffside | Use Power Hammer to break collapsed tunnel | Requires Power Hammer crafting |
The Foundation Route (Recommended)
The Foundation is a permanent room – once drafted, it stays in the same spot forever. Here's how to use it:
- Draft the Foundation anywhere on the map
- To activate its elevator, you need to access its "back wall" (the side with no doors)
- Draft a room adjacent to the Foundation's back wall to reveal a lever
- Pull the lever to enable the elevator
- Ride the elevator down and use the Basement Key on the locked door
Moving the Minecart
A minecart blocks the tunnel between the Reservoir and the Rotating Gear room. You must move it to access all areas of the Underground.
- The minecart can only be pushed/pulled from the south side of the Reservoir
- Access the south side via the Fountain entrance or Tomb entrance
- Pull the minecart all the way back toward you
- Once moved, it stays in that position permanently
Step 5: Pull the North Lever
The north lever is located in the Inner Sanctum, accessible through the Rotating Gear Puzzle area.
Rotating Gear Puzzle
The Rotating Gear room features a massive gear that bridges different ledges. Here's the quickest path to the Inner Sanctum:
- Enter from the Foundation/north side after moving the minecart
- Use the control panel to rotate the gear until a spoke connects your ledge to the ledge directly right
- Walk across and use that control panel to rotate 5 times
- The long spokes should now connect to the Underpass (metal-plated tunnel)
- Walk through the Underpass to reach the Inner Sanctum
Inside the Inner Sanctum, you'll find a circular room with 8 locked doors and a lever in the center. Pull this lever to unlock the north door of the Antechamber.
The 8 doors in the Inner Sanctum lead to post-game content involving Sanctum Keys. You don't need to open them to reach Room 46.
Step 6: Enter Room 46
With the north lever pulled, return to the Antechamber (either by backtracking or starting a new run). The north door – marked with a crescent moon symbol – is now open.
Walk through the door to enter Room 46. Congratulations! Enjoy the cutscene and credits.
Antechamber doors reset every day. You'll need to pull a lever again (east/west/south) to re-enter the Antechamber each run. However, the north door stays unlocked once you've pulled the Underground lever.
Reaching Room 46 is just the beginning. Blue Prince has extensive post-game content with additional puzzles, Sanctum Keys, hidden rooms, and deeper lore. Return to Room 46 on subsequent runs to explore further mysteries.
Pro Tips for Success
- Use Coat Check: Store valuable items (Basement Key, Broken Lever) to preserve them between runs
- Draft Bedrooms: Bedrooms restore steps, helping you explore further each day
- Unlock Permanent Upgrades First: Apple Orchard (+20 steps), Gemstone Cavern (+2 gems) make future runs easier
- Take Notes: Use a physical notebook or screenshot clues – you'll need them later
- Don't Build Straight to Antechamber: Gather resources first, find a lever, then build your path
- The Foyer is Powerful: Unlocks all hallway doors, making Great Hall exploration trivial