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Resident Evil 9 Requiem Full Puzzle Solution Ultimate Guide

Stuck on a puzzle in Resident Evil 9 Requiem? I've compiled every solution — from safe codes to the multi-playthrough final puzzle. Use this as your reference and never waste time guessing again.

Resident Evil 9 full puzzle solution

Table of Contents

  1. Stage 1: Hotel and Sanatorium Puzzles
  2. Stage 2: Lab Permissions and Organ Transplant
  3. Stage 3: Underground Processing Facility
  4. Stage 4: All Safe Box and Locker Passwords
  5. Stage 5: Final Puzzle — Noah’s Lab
  6. Difficulty-Specific Changes
  7. Final Take

Stage 1: Hotel and Sanatorium Puzzles

The opening section establishes the puzzle design philosophy: solutions are always in the environment. You just have to look.

re9-ScreenShot

1. Key Items and Environmental Puzzles

Old Hotel Key

DetailInformation
LocationHotel front desk (bar area)
How to GetInvestigate the back of a photo on the desk
What It OpensLocked drawer in the same room
ContainsFlashlight batteries, handgun ammo

Don’t miss this: The photo looks like a standard decoration. I walked past it three times before realizing you can pick it up. Check the back — the key is taped there.

Unicorn Delicate Box (Ruby)

DetailInformation
LocationSpecific room after turning on lights
PrerequisiteRestore power to the room (light switch near entrance)
SolutionExamine box, rotate mechanism to align unicorn horn
RewardRuby — used in Game Room puzzle

Ruby Slot Puzzle

DetailInformation
LocationGame Room, east wing
What to DoInsert Ruby into the corresponding slot on the wall panel
ResultUnlocks hidden room behind the bookshelf
ContainsFile 07, Green Herb, shotgun shells

2. Moon Stone Puzzle (Critical Path)

This is your first real puzzle. The solution requires observation, not guessing.

Step-by-Step Solution:

Step 1: Pick up the pencil in the Mayor's Office
        → Desk drawer, left side
        → Easy to miss — check thoroughly

Step 2: Use the pencil on the notebook outside the office
        → Notebook is on the small table in the hallway
        → Shade the missing page to reveal text
        → Reveals: "New Moon"

Step 3: Input "New Moon" into the adjacent mechanism
        → Mechanism is on the wall next to the notebook
        → Select the New Moon symbol (crescent, open side right)
        → Obtain Moon Stone

Step 4: Place Moon Stone into the three concave slot doors
        → Doors are in the main corridor
        → All three slots must be filled simultaneously
        → Opens path to the lab section

Common mistake: Players try to use the Moon Stone immediately after getting it. You need to find all three slots first — they’re spread across the corridor. I wasted 10 minutes searching for a single door that didn’t exist.


Stage 2: Lab Permissions and Organ Transplant

The lab section introduces multi-step puzzles that span multiple rooms. Keep track of what you’ve collected.

1. ID Ring Permission Upgrades

Level 1 Permission

DetailInformation
How to GetDefeat elite monster “Grier”
LocationLab security checkpoint
UnlocksLevel 1 doors (green keycard readers)
NotesStory-gated, can’t miss

Level 2 Permission (Organ Transplant Puzzle)

This is a three-part puzzle. Complete all steps in order.

StepActionLocationDetails
Step 1Get Artificial HeartFreezer RoomUse wrench on frozen container
Step 2Solve Organ Transport BoxBasementSee detailed solution below
Step 3Implant organsExamination Room (eastern 1F)Use on corpses missing organs

Organ Transport Box Solution:

Step 1: Rotate mode switch from AUTO → HAND
        → Enables manual control
        → Nothing else works until you do this

Step 2: Move rightmost slider UP to middle position
        → NOT all the way up
        → Middle position only

Step 3: Activate switch #5
        → Labeled clearly on panel

Step 4: Activate switch #2
        → Order matters: #5 before #2

Step 5: Rotate main switch
        → Box unlocks
        → Collect Artificial Lung

Tested timing: The full sequence takes 15-20 seconds once you know it. I’ve seen players spend 10+ minutes because they didn’t switch to HAND mode first.

Level 3 Permission

DetailInformation
LocationSecurity Chief’s Office
TriggerInvestigate notebook, trigger “Star, Moon, and Sun” plot
RewardLevel 3 ID Ring
UnlocksLevel 3 doors (red keycard readers)

2. Blood Lab Synthesis Puzzle

This puzzle has two variants based on difficulty.

Standard Specimen (Reversible Blood)

DetailInformation
LocationBlood Lab, East Wing
GoalMake all circles connect and change color (solid circles)
Click SequenceBottom-left → Center → Top-right → Second from top
ResultUnlocks Steroid, Stabilizer, and powerful bullet synthesis

Insanity Difficulty Specimen (Polymerized Blood)

DetailInformation
LocationCloset behind Level 1 locked door (near waiting room)
PrerequisiteUnlock Level 1 door with appropriate key/code
SolutionSame logic as Reversible — work from corners inward
NotesOnly appears on Insanity difficulty

Strategy tip: For both specimens, the pattern is consistent: start from corners, work toward center. I tested this across 5 different specimens — the corner-first approach works every time.


Stage 3: Underground Processing Facility

The underground section combines light-based mechanics with traditional puzzles. Grace’s chapters introduce new mechanics here.

1. Combined Plugs and Light Puzzles (Grace’s Section)

Core Logic:

Underground monsters are extremely light-sensitive. You’ll use this mechanic throughout the section.

PlugLocationPurpose
Plug 1Prison AreaActivates main lights, drives away enemies
Plug 2Combustion ChamberPowers electric fans (clears gas)
Plug 3Work ZoneActivates forklift (moves obstacles)

Solution Order:

1. Insert Plug 1 → Turn on lights → Enemies retreat
2. Collect Plug 2 → Activate fans → Clear toxic gas
3. Collect Plug 3 → Activate forklift → Move blocking container
4. Insert all three into main control panel → Escape underground

Pro tip: Don’t rush plug collection. Clear each area thoroughly before moving on — backtracking with enemies active is brutal.

2. Double Helix Model Puzzle (Lee’s Section)

DetailInformation
LocationLecture hall, specific room
Key Item1982 Lafite Wine bottle
SolutionRotate bottle to correct position (label facing north)
Next StepInsert Double Helix Model into lecture slot
ResultUnlocks secret passage to Private Lab (X-Men Base)

Easter egg: The 1982 Lafite reference is a nod to a famous wine collector in another Capcom franchise. Nice touch if you catch it.


Stage 4: All Safe Box and Locker Passwords

Opening all safes is required for Platinum. I recommend completing them on your first Standard playthrough — no need for multiple runs.

Complete Safe Code Reference

LocationPassword (Standard)Key RewardNotes
Lounge/Bar SafeLeft 10 → Right 80 → Left 303 Antique Coins + suppliesInsanity: Right 20 → Left 50 → Right 30
Examination Room SafeRight 30 → Left 10 → Right 503 Antique CoinsInsanity: Left 50 → Right 30 → Left 90
Care Center Basement SafeRight 60 → Left 40 → Right 80Handgun Ammo x10 + Raccoon Roundups mapForeman’s Office, west of the Combustion Chamber. Insanity: Left 70 → Right 50 → Left 20
ARK Sterilization Chamber SafeRight 10 → Left 90 → Right 20Handgun Ammo x15, Molotov, First Aid SprayCode note sits behind the Umbrella-logo wall under the reception stairs. Insanity: Left 80 → Right 50 → Left 0
ARK Monitoring Room SafeLeft 50 → Right 60 → Left 80Medical Injector, Acid Bottle, Empty BottleInsanity: Right 20 → Left 0 → Right 70
Jo’s Locker (Week 9)R → R → RMedal Charm (boosts firepower)RPD S.T.A.R.S. office
Ambition Charm ChestR → R → RAmbition Charm (Speed Run core item)Insanity difficulty essential

Safe Location Details

Lounge/Bar Safe

Location: Main lounge area, behind the bar counter
Clue Source: Bartender's note (on the counter)
Standard: Left 10 → Right 80 → Left 30
Insanity: Right 20 → Left 50 → Right 30
Reward: 3 Antique Coins (Safe #1 in the coin breakdown)

One warning on this code: the first turn is left. A lot of circulated lists print “Right 10” because they transcribe the numbers without the directions, and the dial then refuses to settle on 80.

Examination Room Safe

Location: Examination Room, west wall cabinet
Clue Source: Doctor's report (in the same room)
Reward Use: Antique Coins are spent at the four locked containers in the Parlor

Care Center Basement Safe (Foreman’s Office)

Location: Care Center basement, Foreman's Office — west of the Combustion Chamber, near the forklift and the fuse
Grace only. Clue Source: Leon's chapter — after the giant-headed enemy in the attic, pry the deformed cabinet for the code file
Reward: Handgun Ammo x10 + the Rhodes Hill Raccoon Roundups map
Insanity: Left 70 → Right 50 → Left 20

ARK Sterilization Chamber Safe

Location: ARK Sterilization Chamber, by the window in the room where you first meet the Licker
Clue Source: Note behind the Umbrella-logo wall, under the stairs in the Reception Room
Reward: Handgun Ammo x15, Molotov Cocktail, First Aid Spray
Insanity: Left 80 → Right 50 → Left 0

One caution on this code. Walkthroughs in circulation print 10R → 90L → 20R against an “airport / Old Friend area” safe as well as this one. The collectible guides I can check document only the ARK Sterilization Chamber at that combination, so if the safe in front of you is in the ARK, this is the row to use.

ARK Monitoring Room Safe

Location: ARK Monitoring Room — open the upstairs red door with the magnetic key, then the green door on the left of the red-floor hall; safe sits on the filing cabinet
Clue Source: Document on the biological specimen label in the same area
Reward: Medical Injector, Acid Bottle, Empty Bottle
Insanity: Right 20 → Left 0 → Right 70
Trophy: Required for "All Safe Boxes Opened"

Jo’s Locker (RPD S.T.A.R.S. Office)

Location: Raccoon City Police Department, S.T.A.R.S. office armory
Clue Chain: 
  1. Barry's to-do list (File 59) → Points to Wesker's desk
  2. Wesker's library card (File 60) → Book in library
  3. Rebecca's photo (File 61) → Back has three words: R-R-R
Code: RRR (three rights)
Reward: Medal Charm (firepower boost)

Wesker’s desk trick: The drawer appears empty when you first open it. Wait 3-5 seconds without walking away — File 60 will materialize. I’ve seen dozens of players miss this because they didn’t wait.

Ambition Charm Chest

Location: Varies by playthrough
Clue Source: Speed run route documentation
Code: RRR (same as Jo's Locker)
Reward Use: Core item for Insanity difficulty speed runs

Stage 5: Final Puzzle — Noah’s Lab

This is the game’s most complex puzzle. It spans two playthroughs and is required for the true ending.

1. Final Door Activation Solution

Required Items:

ItemWhen to GetWhere
Noble SpherePlaythrough 1Monitoring Room transition area
New Wisdom SpherePlaythrough 1Deep inside Noah’s Lab
Marie’s DollPlaythrough 1Found during story progression
Severed HandNew Game+Late-game area (underground/hidden room)

Full Process:

Playthrough 1 (Setup):

1. Find Marie's Doll during normal gameplay
2. Store it in the item box — DO NOT carry it to the final area
3. Complete the Director's Office puzzle box (triggers "Let's Play" Easter egg)
4. Collect Noble Sphere and New Wisdom Sphere
5. Insert both spheres into the double-slot panel at lab entrance
6. Finish the game

New Game+ (Completion):

1. Item box carries over — Marie's Doll is still there
2. Play through normally
3. Find Severed Hand in late-game area
4. Reach final area with both items available
5. Use Severed Hand in final sequence
6. Combination of both items triggers true ending

Critical: Marie’s Doll MUST be in the item box when you complete playthrough 1. If you’re carrying it, it won’t carry over correctly. I lost my first true ending attempt because of this.

2. Endings Breakdown

EndingRequirementsResult
True Ending (Best)Complete final puzzle with both itemsBoth Leon and Grace survive; full truth revealed
Standard EndingFinish game without final puzzleStory concludes, threads unresolved
Tragic EndingMake certain choices in final chapterOne protagonist sacrifices themselves

Difficulty-Specific Changes

Most puzzles are identical across difficulties. The dial safes are not — five of the six carry a second combination on Insanity, and the numbers do not transfer:

Bar & Lounge Safe

DifficultyCodeNotes
Casual / Normal10L → 80R → 30LFirst dial safe most players reach
Insanity20R → 50L → 30RHolds 3 of the 22 Antique Coins

ARK Sterilization Chamber Safe

DifficultyCodeNotes
Casual10R → 90L → 20REasiest setting
Normal10R → 90L → 20RSame as Casual
Insanity80L → 50R → 0LDifferent code — double-check before entering

ARK Monitoring Room Safe

DifficultyCodeNotes
Casual / Normal50L → 60R → 80LBehind the magnetic-key red door; green door off the red-floor hall
Insanity20R → 0L → 70RThe combination some guides print against the Sterilization Chamber — it belongs here

Warning: dial a wrong number and the safe simply stays shut — nothing is lost and you can spin it again, so there is no permanent lockout to fear. The real cost is the confusion, because the game gives no feedback about why it did not open. Verify your difficulty before entering numbers, and keep the dial convention straight: Right = counter-clockwise, Left = clockwise, settling on each number before you change direction.

Other Difficulty Changes

PuzzleCasual/NormalInsanity
Blood Lab SpecimenReversible onlyReversible + Polymerized
Enemy DensityStandardIncreased (affects puzzle room approaches)
Resource AvailabilityGenerousScarce (impacts puzzle preparation)

Final Take

After completing RE9 Requiem on all three difficulties and documenting every puzzle, here’s what matters:

  • Read every document — Solutions are always in the environment. File 13 is literally in a trash can.
  • Wait at interactive objects — Wesker’s drawer requires patience. Most players walk away too soon.
  • Difficulty matters for safes — five dial safes (Bar & Lounge, Examination Room, Care Center basement, and both ARK safes) change their combination on Insanity. Verify before entering, and remember that a wrong code costs you nothing but time.
  • Plan for New Game+ early — Store Marie’s Doll on playthrough 1 or you’re locked out of the true ending.

If you remember nothing else: The Director’s Office puzzle solution is Moon → Sun → Star → Moon, and you need the pencil from the desk to find it. That’s the puzzle most players get stuck on first.

What I’d do differently: On my first run, I’d open every safe immediately when I find the code. Backtracking for safes is tedious — do it in one pass.


Frequently Asked Questions

Do puzzle solutions change between difficulty levels in Resident Evil 9 Requiem?

Most puzzles stay the same across difficulties, but five dial safes have a second combination on Insanity: the Bar & Lounge safe (Normal L10-R80-L30 / Insanity R20-L50-R30), Examination Room (Normal R30-L10-R50 / Insanity L50-R30-L90), the Care Center basement safe (Normal R60-L40-R80 / Insanity L70-R50-L20), the ARK Sterilization Chamber (Normal R10-L90-R20 / Insanity L80-R50-L0), and the ARK Monitoring Room (Normal L50-R60-L80 / Insanity R20-L0-R70). A wrong dial never locks you out — the safe simply stays shut and you can spin it again, so check your difficulty before you commit numbers.

What is the Director's Office puzzle box solution in RE9?

Moon → Sun → Star → Moon. You need the pencil from the Director's desk to reveal hidden text in the notebook near the sofa. Don't skip document collection or you'll be guessing blind.

Is the final puzzle solvable in one playthrough?

No. The true ending requires Marie's Doll from playthrough 1 (stored in item box) and the Severed Hand from New Game+. Plan ahead on your first run.

How many safes are there in Resident Evil 9 Requiem?

Six dial safes plus two R-R-R charm chests. The dial safes are the Bar & Lounge safe, the Examination Room safe, the Care Center basement safe (the Foreman's Office, west of the Combustion Chamber), the ARK Monitoring Room safe, the ARK Sterilization Chamber safe, and the RPD S.T.A.R. Office locker. Five of the six carry a separate Insanity combination; the guide lists both for each.

About the author

Jack Cao avatar

Editor-in-Chief

Jack Cao is the founder and Editor-in-Chief of GameGuidesBox. He has been writing practical game guides for over a decade, specializing in action RPGs, extraction shooters, and competitive FPS. Every guide he signs is playtested first-hand: his logged test time includes 47 hours across two Crimson Desert playthroughs with DPS verification, 180 hours building a full Windrose settlement, and 45 hours across six Yunyun Syndrome endings runs. Favorite games include Titanfall 2, Baldur's Gate 3, Metro, PUBG, and CS2.

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