The Final Puzzle is an involved mystery that unfolds over multiple playthroughs of Resident Evil Requiem. There are several specific steps for Grace to accomplish in the Care Center.
This guide for Resident Evil Requiem details everything you need to do in order to solve The Final Puzzle.
Rhodes Hill – Care Center Basement
Once you arrive at the Processing Room in the Care Center Basement, do not empty the pool just yet. Instead, allow precisely 115 bodies from the conveyor system to drop into the pool over a span of fifteen minutes.
This oddly specific number is based on a clue from the file title ‘Subject 170 Record’, referring to Marie, and that you will actually find later on in the game when you make your way to the Care Center Courtyard. It is located on the gurney by the exit to Collection & Testing.
Leaving the room will throw the count off, as will shooting or killing any zombies. Make use of the save point to be safe.
Use the valve now, and drain the pool, then climb down into it.
Allow the grinder to do its job without any intervention. Once again do not shoot or kill any zombies.
Make your way to the Collection Pool and drop the heavy switch labeled Collection & Testing in order to drain the blood pool. This step is simply to be sure that the previous two steps were done correctly.
If the caption states that ‘A ton of blood flowed out’, then you were successful. On the other hand, if it reads as ‘A lot of blood flowed out’, then you have failed one of the steps and will need to start over from a save made before the corpses drop.
Rhodes Hill – Care Center
Back in the Care Center’s Central Hall, proceed to the Restroom. Select a toilet, any will do, and flush it exactly eight times in a row.
This step cannot be validated in-game like the previous one.
Rhodes Hill – Care Center Courtyard
After acquiring the Helicopter Key in the Private Lab, but before making your high stakes escape, pass through the Collection & Testing room. The blood orb here will explode into a flood of blood. Marie’s Doll can be found by heading left through the room, at the base of some stairs.
The previous steps were all in service of getting this key item to spawn here, so be sure to hold on to it for the next playthrough.
Second Playthrough of Rhodes Hill – Care Center
After the cutscene in the elevator, and receiving the Star Quartz, turn around and recover the Severed Hand off of the floor.
Take it to the Blood Lab and use the Laser Microscope to analyze it.
This puzzle is similar to the other Blood Specimen puzzles.
Select the cube on the far right first, then the one on the far left. The last selection is the atom in the dead center of the molecule.
Once solved, you will see a message that reads ‘Let’s play’, followed by the cipher GGC AAG AUA ACG UGU CAU.
This step also activates the Lead Researcher’s Office Puzzle Box again.
You do not need to collect the following clues, but these explain why they matter in the puzzle solution.
When examining the Laser Microscope you will see ‘G = 150000000’ (one hundred and fifty million). The Sun is approximately that distance away, therefore G denotes ‘Sun’ in the cipher.
Second Playthrough of Rhodes Hill – Care Center Courtyard
The next clue is the hourglass on the desk in the VIP Suite. Examine it in order to turn it over and empty the sand out, at least enough to read the imprint on the base, which is ‘U = 380000’ (three hundred and eighty thousand). The Moon is approximately that distance away, therefore U denotes ‘Moon’ in the cipher.
The third clue involves the file ‘Grace Ashcroft Blood Analysis Report’ that is lying on the desk in the Private Lab, wherein it is stated that ‘C = 4.2 ly’ at the very bottom. Proxima Centauri, the nearest star, is approximately that distance away, therefore C denotes ‘Star’ in the cipher.
Second Playthrough of Raccoon City – Raccoon City Center
Make your way to the Basketball Court in the north. Carefully manoeuvre the large figure head in the center of the court through the fallen basketball hoop by walking into it, which will make the latter interactable.
The caption will state ‘There’s no time for playing around.’
Return to the Gun Shop Kendo through the locked gate, and interact with the decapitated body of the figure head amidst the new debris inside, to the immediate left of the doorway.
The caption will state ‘Just ignore A.’ Therefore A denotes nothing in the cipher.
Second Playthrough of Rhodes Hill – Care Center
In the Lead Researcher’s Office with both Marie and Marie’s doll in your possession, the manually inputted code for the Lead Researcher’s Office Puzzle Box is:
- Sun
- Sun
- Star
- Sun
- Moon
- Star
- Sun
- Moon
- Sun
- Moon
- Star
- Moon
This corresponds to GGC GUC GUG UCU from analyzing the Severed Hand, with the A’s excluded. The creepy laugh you hear will audibly validate your entry.
Those are all the steps to solving the complex challenge known as The Final Puzzle in Resident Evil Requiem.
