Cthulhu: The Cosmic Abyss Wiki

Cthulhu The Cosmic Abyss — Chapter 1: Awakening

May's house, clue hunt, basement mechanism — demo-complete awakening arc.

Clues & collectibles

  • Potted plant
  • Article
  • Obituary
  • Medicine bottle
  • Arkham Observer
  • Quartz alloy
  • Opera mask
  • PIT Incident Report
  • Occult pages
  • Basement blood
  • William Shippen letter
  • Basalt behind pillow

Step-by-step

  1. 1. Arrival at the locked house

    After the intro cutscene you reach May's locked house by boat. Listen to Elsa (KEY) for context. Your investigation and clue scanning begin here.

  2. 2. Entrance — potted plant

    To the left of the front door, move the potted plant. Duck or crawl through the gap you reveal. Discuss the flooding with KEY when prompted.

  3. 3. Roof access

    Climb the tree to reach the roof hole and enter the house. Optional: talk with KEY for extra dialogue.

  4. 4. Table article

    On the table, unfold the article completely to register the first major clue, then return it to your inventory flow.

  5. 5. Bedroom

    Inspect Mei's photo (parents Fen and Yahui). Read the obituary on both sides — it counts as a separate clue for KEY.

  6. 6. Bathroom

    Pick up the medicine bottle on the floor for another scannable clue.

  7. 7. Living room

    Check the drawing near the mirror wall (discuss with KEY). Read the Arkham Observer from July 2051.

  8. 8. Office

    Review wall inscriptions and Yahui's diploma. Agree to the Noah file. In the cabinet, note the opera mask inscribed 'Jia Wei 1892'. On the desk: classified folder, PIT Incident Report (check the back), and Mei's cassette.

  9. 9. Shelves

    Collect occult book pages. Pick up the quartz alloy and scan it with sonar on the Mineral frequency when KEY allows.

  10. 10. Kitchen and basement

    Kitchen: inspect trash bags and the Arkham paper from January 2053. Basement: examine the blood-stained table and William Shippen's letter — corruption pressure starts to rise here.

  11. 11. Mechanism puzzle

    Find basalt hidden behind a pillow. Combine basalt and quartz in the basement mechanism to finish the chapter.

Video

Sanity tips

First major corruption spike is tied to the basement blood scene. Avoid staring at anomalies too long. Roughly 12 of 25 clues for Thanks Key can be completed in this chapter — see the achievements page for the full list.

More in Sanity guide and achievements.

FAQ

How do I unlock Thanks Key?

Have KEY analyze 25 distinct clues. Chapters 1 and 2 of the demo contain more than half of them if you scan thoroughly.

Where is the quartz alloy?

Near the occult book pages on the shelves in May's house. Scan it on the Mineral sonar frequency when KEY unlocks that step.

I missed a clue — can I go back?

Most demo areas allow free backtracking inside the chapter. If a door locks, reload an earlier save if available.

Hardest achievement in the demo?

Thanks Key or full frequency coverage — both reward slow, methodical scanning.