For the Tenebris Somnia achievements, keep Wrench Queen and Exhaust Pipe on separate save branches: one requires a wrench-only game clear, the other a pipe-only Fumus kill. Knock on Iván's door ten times for Maybe He's In The Bathroom, and inspect his picture five times for Thinking About Him, huh?
Separate the weapon challenges first
Save before Fumus, take the pipe-only kill on one branch, then reload the untouched save for your wrench-only continuation. Defeating Fumus with the pipe and carrying that result forward would break the wrench-only requirement. These Tenebris Somnia achievements need different continuing attempts, even when you use the same earlier save to begin them.
Classics Never Die is a pickup objective, not a combat restriction. Use the screwdriver to obtain the iron pipe in the bar bathroom. Collecting it and attacking with it are different actions: the pickup earns its own achievement, while using the pipe to defeat Fumus belongs on your separate branch.
Iron and wax is narrower than Wrench Queen. It restricts the Obscuratus fight to the wrench, while Wrench Queen applies to the game clear. A wrench-only boss victory does not establish that you used only the wrench elsewhere in the run.
Match each interaction to its counter
Tenebris Somnia achievements distinguish repeated interactions from item use. The door objective counts knocks on Iván's door, whereas the picture objective counts looks at his picture. For One More For The Road, the deciding condition is your health when you drink Lavendoleum: use it while your health is already full, not after taking damage.
Have You Chosen... Wisely? asks you to fill the silver bottle by removing three save points. That objective consumes save points rather than merely asking you to visit them. Decide which continuing branch you want to keep before pursuing a task whose stated action removes places to save.
Complete the collection objectives
For Stella Plena, open all star lockers. Collecting keys alone is not the stated objective; the containers themselves must be opened. Devora instead asks for all three film canisters, while De Relictis asks you to read every page of the old book. Finding a book and reading its pages are not interchangeable actions.
For these Tenebris Somnia achievements, keep the old book separate from the Bible used for the alternate ending puzzles. De Relictis concerns reading the old book's pages, not using the Bible at a television or combination puzzle.
Handle the encounter-specific objectives
During Obscuratus's candle encounter, extinguish the candles to create an opening to attack. Keep that damage wrench-only if you want Iron and wax. For Exhaust Pipe, the weapon condition belongs to Fumus instead: defeat him using only the pipe, on the branch reserved for that challenge.
The two multi-kill Tenebris Somnia achievements use different targets. The Two Stooges requires two or more enemies at once and explicitly excludes Carnitos. Valiant Little Taylor requires three Carnitos with one hit. Butcheress is a separate Carnitos objective: defeat them without getting hit, rather than treating a successful multi-kill as a no-damage clear.
For Bad Puppy, Sanguis must break all the mannequins. Simply defeating him does not fulfill that destruction objective. For He Just Wanted a Hug, escape a Vorax into another room before it explodes; the room transition is part of the task, not merely putting distance between you and the enemy.
Acrophobia explicitly requires death after Lacuna drops you, so surviving the drop is not the target. Devoured asks you to get eaten by Hermes. Keep a separate pre-fight save if you also want to continue the run, rather than replacing your continuing attempt with a deliberate encounter objective.
Use the complete achievement checklist
The Tenebris Somnia achievements list contains 24 entries. Use the exact objective below to identify whether you are missing an interaction, collectible, encounter condition or ending. In particular, the wrench-only game clear and wrench-only boss kill occupy different rows.
| Achievement | Objective |
|---|---|
| Maybe He's In The Bathroom | Knock on Iván's door ten times. |
| Thinking About Him, huh? | Look at Iván's picture five times. |
| One More For The Road | Drink Lavendoleum at full health. |
| Classics Never Die | Pick up the iron pipe. |
| Stella Plena | Open all star lockers. |
| Devora | Find all three film canisters. |
| Have You Chosen... Wisely? | Fill the silver bottle by removing three save points. |
| De Relictis | Read all pages of the old book. |
| The Two Stooges | Kill two or more enemies at once, excluding Carnitos. |
| He Just Wanted a Hug | Escape a Vorax into another room before it explodes. |
| Iron and wax | Defeat Obscuratus using only the wrench. |
| Exhaust Pipe | Defeat Fumus using only the pipe. |
| Valiant Little Taylor | Kill three Carnitos with one hit. |
| Butcheress | Defeat the Carnitos without getting hit. |
| Bad Puppy | Make Sanguis break all mannequins. |
| You Can Stop Now | Keep walking down the endless corridor. |
| Heart of Lead | Kill all Relicta ghosts. |
| Acrophobia | Die after being dropped by Lacuna. |
| Devoured | Get eaten by Hermes. |
| Wrench Queen | Complete the game using only the wrench. |
| SOLVE ET COAGULA | Get Ending #1. |
| MAGNUM OPUS | Get Ending #2. |
| VIVUS EX MORTIBUS | Get Ending #3. |
| RENUNTIATIO | Get Ending #4. |
Separate ghost cleanup from ending completion
Heart of Lead requires all Relicta ghosts, not just the one kill sufficient for MAGNUM OPUS. When planning Tenebris Somnia achievements, keep the no-kill Aurifer save intact for SOLVE ET COAGULA and use a different continuation for ghost cleanup. An ending unlock is not a substitute for the all-ghosts requirement.
For the alternate Bible route, complete Ending #1 and Ending #2, start a new game, and collect the Bible for its alternate puzzles. For RENUNTIATIO, turn around at the start of a new game and use the apartment keys at the building entrance. Those are separate opening actions with different destinations.