✦ Craft & Quest

Tenebris Somnia · A.S. door key

How to get the key stuck inside the A.S. door

On this page
  1. Bring these three items
  2. Open the blue-symbol door, then find A.S.
  3. Use the tools at the door
  4. If you are still missing the key
  5. Sources and version

Use the Scissor Blade and then the X-Ray at the A.S. door. You first need the blue Triangular Stone to enter the room leading to that door. The Scissor Blade and X-Ray are found back in the apartment.

Published October 20, 2026 · Full PC release · Puzzle spoilers for this section

Bring these three items

Blue Triangular Stone
After speaking with Sanguis, take it from the candle arena, to the right of the red candle.
Scissor Blade
Pick it up from the kitchen countertop.
X-Ray
Look on the short bookshelf directly below the apartment’s front door, between the picture frame and lamp.

Before leaving the apartment, check the inventory for both tools. That avoids returning through the hallway after discovering you brought the blade but missed the X-Ray.

Open the blue-symbol door, then find A.S.

  1. Leave the apartment and walk towards the green Floor 2 elevator.
  2. Stop at the blue door bearing a symbol.
  3. Use the blue Triangular Stone to enter.
  4. Inside, go to the leftmost door marked A.S. Look for the red carpet protruding underneath.
Julia at the A.S. door in the waiting room with a red carpet protruding underneath
The target is the A.S. door on the far left. The carpet beneath it is the useful landmark when identifying the key puzzle. Source: Developer’s Official Puzzle & Boss Guide. Game © Andrés Borghi / Saibot Studios / New Blood Interactive. Select for the full image.

Use the tools at the door

Stand directly in front of A.S., open the inventory and use the Scissor Blade. Then use the X-Ray at the same door. The developer’s route lists the tools in that order and awards the A.S. Key after the interaction.

Tenebris Somnia inventory showing the Scissor Blade selected with Use and Combine commands
The inventory distinguishes Use from Combine. This puzzle applies tools to the door; it does not ask you to combine the blade and X-Ray into a new inventory object. The key has not yet been awarded in this frame. Source: Unmutual’s demonstration linked by the developer, 1:21. Game © Andrés Borghi / Saibot Studios / New Blood Interactive. Select for the full image.

If you are still missing the key

Check the current obstacle first. If you cannot enter the symbol door, revisit the Triangular Stone. If you are already in the waiting room, identify A.S. by the carpet and apply the two tools there.

Recheck the kitchen counter and the low bookshelf if either tool is absent. A similar-looking item in another room is not a substitute. After completing the door interaction, confirm that A.S. Key appears before travelling elsewhere.

Keep the Scissor Blade in mind for the next area: the director’s office supplies a second blade for the Scissors and Devora poster puzzle.

Sources and version

Checked October 20, 2026 against the developer’s official guide, Key Stuck in Door Puzzle and its linked Unmutual video walkthrough. Screenshots are limited instructional excerpts from those sources, not our own playthrough. Official 1.0.1 patch notes.

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