Lapis Fictus Knife puzzle (Desiderium apartments)

Where the puzzle is

The Desiderium is the corrupted version of the building that you enter after meeting Sanguis on the film set. This chain runs through its 2nd- and 3rd-floor apartments and the 2nd-floor film offices.

The Old Book warns that the Lapis Fictus is a shortcut that promises to purify you, and repeats the Auritsatio recipe from the first door. Here the blood goes in a Glass Vase instead of a glass, and the light comes from the studio light.

Not sure you’re in the right place? Search for your room in Quick find tool.

What you need

• Glass Box: the Desiderium 2nd-floor apartment bedroom
• Photographs: the clothes rack in the 2nd-floor office
• Glass Vase: smash the vase in the 3rd-floor office
• Film Canisters: the three DEVORA canisters you collected earlier in the game
• Lighter: already in your inventory from the film offices (to light the oven)
• Circular Plate: on the kitchen table after the oven step
• VHS Tape: the chest in the 2nd-floor office (opened with the Circular Plate)
• Julia's Figurine: the 2nd-floor office
• Iván's Figurine: on the TV screen after the VHS fight

Exact spots for each one are on Items and collectibles.

Step by step

1. Prepare the 2nd-floor apartment

   In the Desiderium 2nd-floor apartment, turn on the bathroom sink and interact with the Iván statue. Take the Glass Box from the bedroom and the Photographs from the office clothes rack.

2. Break into the bathroom from the stairwell

   Break the damaged wall in the stairwell. It lets you into the bathroom and on through to the kitchen.

3. Make the blood vase

   In the 3rd-floor office, smash the vase to get the Glass Vase. Fill it with blood, then combine it with the Film Canisters.

4. Solve the poem wall

   Place the four photographs on the numbered wall in the 3rd-floor apartment. The first sentence of the poem picks the set; see the poem photographs puzzle page for the table.

5. Bake the vase, open the chest

   Put the vase in the 2nd-floor oven and light it. Take the Circular Plate, use it on the chest in the 2nd-floor office to get the VHS Tape, and pick up Julia's Figurine.

   

6. Play the VHS Tape for Iván's Figurine

   Play the tape on the TV in the 3rd-floor apartment and win the fight on the screen. Iván's Figurine is then on the TV; take it.

7. Fill the Glass Box and gild the statue

   Combine both figurines with the Glass Box. Use it on the statue past the A.S. door, and smash the statue once it turns gold.

8. Make Auritsatio and free the knife

   Use the vase on the studio light to turn it into Auritsatio. Use the Auritsatio on the Iván statue and take the Lapis Fictus Knife.

If it doesn’t work

The oven won't take the vase.

The vase needs blood in it and has to be combined with the Film Canisters first. Then put it in the 2nd-floor oven and light the oven with the Lighter.

The statue past the A.S. door doesn't turn gold.

Both figurines must be inside the Glass Box. Julia's Figurine is in the 2nd-floor office; Iván's only appears on the TV after you win the VHS fight.

I can't reach the 2nd-floor kitchen.

Break the damaged wall in the stairwell. It leads into the bathroom and through to the kitchen.

Sources

1. Tenebris Somnia - All Puzzles & Solutions Guide by iampanax Timestamps used: 41:19–50:10
2. Tenebris Somnia Full Game Walkthrough - All 4 Endings [No Commentary] by iampanax Timestamps used: 3:35:31