The Sturdy Padlock on the Sun Puzzle Box inside the Lead Researcher’s Office is one of the first progression blockers you will hit during Grace’s section of Resident Evil Requiem. Bullets, knives, and brute force will not break it — you need a specific key item called the Corrosive to dissolve the lock. This guide covers exactly where to find the Corrosive bottle, how to safely navigate past the Chunk enemy to reach it, and the full puzzle box solution once the padlock is removed so you can claim the Sun Quartz and continue your escape from the Rhodes Hill Care Center.
⚡ Quick Answer
To destroy the Sturdy Padlock in the Lead Researcher’s Office, you need the Corrosive — a blue bottle found on a cabinet in the back room of the Conference Room on the 2nd floor of the East Wing. Grab it, return to the puzzle box, inspect the padlock, and select the Corrosive to melt it. Then enter the code Star – Sun – Moon – Sun to open the box and obtain the Sun Quartz.
Where Is the Sturdy Padlock?
The Sturdy Padlock is located inside the Lead Researcher’s Office on the 2nd floor of the East Wing of the Rhodes Hill Chronic Care Center. You will reach this area after obtaining the East Wing Keycard from the Parlor and heading upstairs.
Inside the office, you will find a Sun Puzzle Box sitting on a desk — similar to the Moon Puzzle Box you solved in the Chairman’s Office. However, unlike that puzzle box, this one has a heavy padlock physically locking it shut. You cannot interact with the dials or input any code until the padlock is removed.
A note on the desk from the Lead Researcher confirms that the padlock’s key has been lost and suggests using a corrosive substance stored in the Conference Room to dissolve the lock instead. This is your next destination.
Pick up the Lockpick on the dresser near the typewriter — it is easy to miss. Also inspect all the framed photographs in both rooms. These photos contain the visual clues you will need for the puzzle box code later.
Where to Find the Corrosive Bottle
The Corrosive is located inside the Conference Room on the 2nd floor of the East Wing, down the western corridor from the Lead Researcher’s Office. It is a blue bottle sitting on a cabinet along the west wall of the Conference Room’s back (south) section.
Map showing the Corrosive bottle location in the Conference Room — East Wing, 2nd Floor
However, getting to the Conference Room is not as simple as walking down a hallway. Two major obstacles stand between you and the Corrosive: the Chunk mini-boss enemy that patrols the corridor, and a room full of zombies including a dangerous Siren (singing zombie) inside the Conference Room itself.
The Corrosive bottle on a cabinet in the back section of the Conference Room
How to Get Past the Chunk Enemy
When you exit the Lead Researcher’s Office, you will first need to pick up the ID Wristband (Level 1) from the corpse at the end of the hallway to the left. Grabbing the wristband triggers a cutscene that introduces Chunk — a massive, bloated monster that will begin patrolling the East Wing’s upper floor corridors.
Chunk blocks the path between you and the Conference Room. You have three options:
Option 1: Bait and Evade (Recommended for Most Players)
Lure Chunk down the corridor toward the stairwell, then quickly duck into the Lead Researcher’s Office or the Waiting Room. Wait for the creature to wander downstairs or to another area, then sprint to the Conference Room while the hallway is clear. This costs no resources and is the safest approach.
Option 2: Kill Chunk with Hemolytic Injectors (3 Required)
If you have crafted Hemolytic Injectors, you can stealth-kill Chunk by sneaking up behind it and injecting it three times. Wait in the Waiting Room or Examination Room, let Chunk pass, then follow behind and inject. Repeat three times. Killing Chunk rewards you with the Eye Spy Charm, which increases Grace’s chance of surviving fatal damage — a powerful defensive bonus.
Option 3: Kill Chunk with the Requiem Revolver
Two to three headshots with the Requiem revolver will put Chunk down. This method is faster but burns through your scarcest ammo type. Only do this if you have spare Requiem bullets and Rare Metal to craft more.
Killing the Chunk as Grace earns the “Grace and Goliath” challenge and the Eye Spy Charm. You must do this before reaching the Isolation Ward — once you switch to Leon’s perspective again, Chunk disappears permanently.
Conference Room Walkthrough
Once you have gotten past Chunk and entered the Conference Room, prepare for a fight. The room contains two to three standard zombies and one Siren (singing zombie in a white dress). The Siren’s scream can stagger Grace and attract nearby zombies, making her the priority target.
A single Requiem headshot will kill the Siren instantly. This is worth the ammo investment because her scream will make the fight significantly harder if she stays alive. Alternatively, use a Hemolytic Injector if you can stagger her first.
After clearing the enemies, move to the back (south) section of the Conference Room. Look along the west wall for a cabinet with a blue bottle sitting on top — this is the Corrosive. Pick it up and add it to your inventory.
The Corrosive bottle — your key to destroying the Sturdy Padlock
While you are in the Conference Room, also grab the Antique Coin on the white desk near the entrance and any ammo or crafting materials dropped by the defeated zombies. The Siren will drop another Antique Coin when killed.
The Siren here is the second of two singing zombies in the Care Center. If you killed the first one in the Bar & Lounge area of the West Wing, defeating this one completes the “Deadly Duet” challenge.
How to Destroy the Sturdy Padlock
With the Corrosive in your inventory, head back to the Lead Researcher’s Office. Be cautious in the corridor — Chunk may still be patrolling if you chose to evade rather than kill it.
Enter the Lead Researcher’s Office and go to the back room where the Sun Puzzle Box is located.
Inspect the Sturdy Padlock on the puzzle box by interacting with it.
When prompted, select the Corrosive from your inventory.
A short animation will play showing the acid dissolving and destroying the padlock.
The puzzle box dials are now exposed and ready for you to input the code.
The Corrosive dissolves the Sturdy Padlock, exposing the puzzle box dials
A brief cutscene will trigger when you re-enter the Lead Researcher’s Office with the Corrosive. This is a story beat — let it play out, then proceed to use the Corrosive on the padlock.
Sun Puzzle Box Solution: Star, Sun, Moon, Sun
With the padlock destroyed, the puzzle box has four dial positions and three possible symbols for each: Sun, Moon, and Star. The correct combination is:
| Dial 1 (Left) | Dial 2 | Dial 3 | Dial 4 (Right) |
|---|---|---|---|
| ⭐ Star | ☀️ Sun | 🌙 Moon | ☀️ Sun |
How to Find the Clue In-Game
The code is hidden across two framed photographs inside the Lead Researcher’s Office. One photo shows the first two symbols (Star and Sun) visible on the puzzle box in the background, and the other shows the last two (Moon and Sun). You should have already added these photos to your files when you first visited the office.
This combination is the same on all difficulty levels, including Casual, Standard, and Insanity. Unlike safe codes, puzzle box solutions do not change between difficulties in Resident Evil Requiem.
Rewards: Sun Quartz and Leatherbound Notebook
Opening the Sun Puzzle Box gives you two critical items:
| Item | Purpose |
|---|---|
| Sun Quartz | One of three Quartz gems (Moon, Sun, Star) required to open the locked door in the Central Hall and escape to the Courtyard. Insert it into the Quartz Door above the reception desk. |
| Leatherbound Notebook | Contains instructions for opening the Organ Transport Box, which holds the Artificial Lungs needed to progress. The solution involves switching the dial to HAND, setting the right switch to middle level, pressing Button 5, then Button 2, and resetting the dial to AUTO. |
You need two free inventory slots to pick up both items. If your inventory is full, head to the Storage Box in the Guard Office on the 1st floor to free up space before opening the puzzle box.
What to Do After Getting the Sun Quartz
After collecting the Sun Quartz and Leatherbound Notebook, here is the progression path:
Return to the Central Hall and insert the Sun Quartz into the Quartz Door above the reception desk. You now have two of three Quartz gems.
Head to the Guard Room on the 1st floor and use the Leatherbound Notebook instructions to open the Organ Transport Box for the Artificial Lungs.
Bring the Artificial Lungs to the Examination Room and place them on the corpse. This triggers a fight and drops the ID Wristband (Level 2).
Use the Level 2 Wristband to unlock the Isolation Ward and begin the search for the final Star Quartz.
If you have not already done so, this is also a good time to open the Examination Room Safe (code: Right 30 – Left 10 – Right 50 on Standard difficulty) for three Antique Coins, and to use any remaining Lockpicks on locked drawers for Rare Metal.
You will also want to make sure you have found the Care Center Fuse and the West Wing Keycard if you have not picked them up yet.
Frequently Asked Questions
Can I shoot the Sturdy Padlock to break it?
No. The padlock cannot be destroyed with any weapon — not the pistol, Requiem revolver, or knife. The only way to remove it is by using the Corrosive found in the Conference Room.
Where exactly is the Corrosive in the Conference Room?
It is in the back (south) section of the Conference Room, sitting on a cabinet along the west wall. You must clear the zombies and Siren in the room before safely picking it up.
Do I have to kill the Chunk to reach the Conference Room?
No. You can bait Chunk away from the corridor by luring it toward the stairwell, then sneak past while it wanders. However, killing Chunk with 3 Hemolytic Injectors rewards the valuable Eye Spy Charm.
Is the puzzle box code the same on Insanity difficulty?
Yes. The puzzle box solution (Star – Sun – Moon – Sun) is identical on all difficulty levels. Only safe codes change between Standard and Insanity in Resident Evil Requiem.
What do I get from opening the Sun Puzzle Box?
You receive the Sun Quartz (needed to open the Central Hall door) and the Leatherbound Notebook (instructions for the Organ Transport Box puzzle).
I do not have enough inventory space. What should I do?
Head to the Storage Box in the Guard Office on the 1st floor of the East Wing to deposit items before opening the puzzle box. You need two free slots.
