RE9 Final Puzzle Walkthrough: ARK Laboratory
The RE9 final puzzle is the last major brain-teaser in Resident Evil 9: Requiem, located deep within the ARK Laboratory. This multi-stage puzzle requires you to operate a DNA sequencer terminal, align molecular chains, and activate the reactor to open the path to the final boss encounter. The RE9 final puzzle is the most complex challenge in the game, combining elements from previous puzzles into one climactic sequence.
This walkthrough breaks down each stage of the final puzzle with clear step-by-step instructions so you can solve it without frustration and prepare for the endgame.
⚠️Point of No Return
Completing the final puzzle triggers the endgame sequence. Make sure you have collected all optional items, solved all previous puzzles, and saved at the typewriter in the ARK lobby before starting. There is no going back after the reactor activates. Check the Mr. Raccoon locations guide to verify you have all collectibles.
Where to Find the Final Puzzle
The final puzzle is located in the ARK Central Core, the deepest section of the laboratory. You reach it after progressing through the Bio-Research Wing, Server Room, and Containment Area. The Central Core is a large circular room with a massive reactor in the center and a DNA sequencer terminal on the east wall.
You gain access to the Central Core after using the ARK Access Card Level 3, which you obtain from solving the Lead Researcher's puzzle box earlier in the ARK section.
Stage 1: DNA Sequencer Terminal
The first stage involves the DNA sequencer terminal. When you interact with it, a screen displays four molecular chains that need to be rearranged into the correct sequence.
How the Sequencer Works
The terminal shows four horizontal bars, each representing a DNA strand segment. Each bar can be moved up or down to different positions. The goal is to arrange them so the connecting nodes between bars align perfectly, forming a continuous double helix pattern from top to bottom.
| Position | Bar | How to Identify |
|---|---|---|
| 1 (Top) | Bar C | 3 nodes on the left side |
| 2 | Bar A | 2 nodes evenly spaced |
| 3 | Bar D | 4 nodes clustered together |
| 4 (Bottom) | Bar B | 2 nodes on the right side |
Stage 2: Reactor Alignment
After completing the DNA sequencer, the reactor in the center of the room partially powers up. Three alignment rings around the reactor begin rotating slowly. You need to lock each ring into position by interacting with the three alignment consoles spaced around the room.
Console Locations
The three consoles are positioned at the north, southeast, and southwest sides of the circular room. Each console controls one ring of the reactor.
📝Order Does Not Matter
You can lock the three reactor rings in any order. Each console operates independently. If you lock a ring incorrectly, interact with the same console again to release it and try once more.
Stage 3: Final Activation
Once all three rings are locked, return to the DNA sequencer terminal and interact with it one final time. A confirmation prompt appears asking you to initiate the reactor sequence. Confirming this triggers a cutscene where the reactor fully powers up, opening the reinforced blast door on the north side of the Central Core.
This blast door leads directly to the Final Corridor and the ultimate boss encounter. Make sure you are fully prepared:
- Full health and healing items
- Plenty of ammunition for your strongest weapons
- The Magnum or Requiem Revolver loaded and ready
- Any remaining consumable items allocated in your inventory
Tips for the Final Puzzle
- Save before starting. The typewriter in the ARK lobby is your last save point. Use it before entering the Central Core.
- The DNA sequencer has no penalty for errors. You can rearrange the bars as many times as needed. Take your time to identify each bar by its node pattern.
- Reactor rings have generous timing. Each ring pauses at the correct position for about 2 seconds. Even with slow reaction time, you should be able to lock them on the first or second revolution.
- Bring a weapon into the Core room. Although no enemies appear during the puzzle itself, a brief combat encounter triggers after the blast door opens before you reach the final boss arena.
Connection to Previous Puzzles
The RE9 final puzzle serves as a culmination of the game's puzzle design. The DNA sequencer directly references the double helix motif introduced in the VIP Suite. The reactor alignment shares mechanical similarities with the recessed panel orb rotation. Even the celestial symbolism from the moon puzzle appears in the reactor ring markers (blue for moon, red for sun, green for star).
This thematic connection rewards players who paid attention to earlier puzzles and reinforces the story's focus on biological experimentation and DNA manipulation.
Frequently Asked Questions
Can I leave the Central Core after starting the final puzzle?
Yes, you can leave the Central Core at any point before confirming the final activation in Stage 3. Your progress on the DNA sequencer and reactor alignment is saved. However, once you confirm the activation, the sequence is irreversible.
Does the final puzzle change on Insanity difficulty?
The puzzle itself is identical on all difficulties. The only difference is that the combat encounter after the blast door opens features stronger enemies on Insanity mode. The DNA sequencer and reactor alignment solutions remain the same.
What if I cannot identify which bar is which in the DNA sequencer?
Each bar has a unique node pattern. Bar A has 2 evenly spaced nodes, Bar B has 2 nodes clustered on the right, Bar C has 3 nodes on the left, and Bar D has 4 nodes clustered together. Hover over each bar to highlight it and count the nodes before moving it.
Is there anything missable in the ARK Laboratory?
Yes. Mr. Raccoon #25 is on a windowsill in the Final Corridor after the blast door opens. Make sure to grab it before entering the boss arena. Check our Mr. Raccoon guide for details. Also verify that you have opened the ARK safe in the Director's Office.
With the RE9 final puzzle complete, the reactor is online and the path to the final confrontation is open. Brace yourself for the climactic boss fight ahead. For a complete list of every puzzle in the game, visit the puzzle solutions hub, and make sure you have grabbed all collectibles before the point of no return.