20 articlesIf you’re tired of Grace’s shaky aim or her “one-hit-from-death” health pool, you need to make a beeline for the Blood Lab. The RE games love a good laboratory puzzle, and Resident Evil Requiem is no different. The Blood Specimen Reversible puzzle is one of the most important in the game because it’s your ticket to permanent stat upgrades.
In this guide, I’ll show you how to find the specimen and solve the analyzer puzzle in the minimum 4 steps. Let’s dive in!
Where to Find the Specimen
Before you can even think about the puzzle, you need the ID Wristband (Level 1). You can find it near a dead body outside the Lead Researcher’s Office.
If you’ve got that, head over to the Blood Lab.
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- Enter the Lab: Use your wristband to bypass the security door.
- Scavenge: Inside this first room, keep your eyes peeled. You’ll find your first Empty Injector (don’t lose this!) and the Blood Specimen (Reversible) sitting in the corner.
3. Head to the Analyzer: Go into the adjacent room—the main blood lab—and interact with the large analyzer machine. Slot the specimen in to start the minigame.
The Atom Conversion Puzzle (4-Step Solution)
The puzzle features a molecular structure with “nodes” that are either Round or Square. When you click an atom, it flips its shape—but it also flips every atom it’s directly connected to. Your goal is to get the whole thing to be Round.
The game tells you the minimum is 4 steps. If you want to get it done without the trial-and-error headache, follow this sequence:
- Corner Cleanup: You’ll notice a cluster of three squares in a corner. Hit the center node of that specific cluster to eliminate them.
- Hit the Center: Select the center cube node. This resets the core and leaves you with a specific cluster of squares.
- The Outer Edges: You should be left with four square nodes. Target the corner cubes on each side that are not connected to the center.
- The Final Flip: Once the first corner is changed, you’ll have three connected square nodes left. Select the center of those three, and the entire molecule will convert to round.
Pro Tip: If you mess up the order, just back out of the machine and re-interact to reset the puzzle to its default state so these steps work perfectly.
If you’re still figuring out how crafting works, you can check out our how to craft with blood collector guide.
Rewards: Steroids and Stabilizers
Solving this puzzle isn’t just for a trophy; it unlocks the most powerful crafting station for Grace. You can now use those Empty Injectors you find throughout the game to create:
- Steroids: These provide a permanent increase to your maximum health.
- Stabilizers: These provide a permanent boost to your reload speed and aim stability.
In a game where every bullet and every health point counts, these are literal lifesavers.
Wrap Up
In a survival horror game where resources are tight, these permanent upgrades are the biggest advantage you can get. Instead of burning through herbs and first aid sprays, you’ll actually be able to tank a few hits and land your headshots more consistently. Just make sure you keep an eye out for more Empty Injectors as you explore the rest of the facility—each one is a chance to make Grace even stronger.
