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The Sinking City 2 All Keys and the Doors They Open

Last verified · TSC2 Wiki

The Sinking City 2 uses named keys rather than a generic lockpick, and each one opens a specific door in the chapter that gives it to you. The table below lists every key we have logged, the chapter it appears in and what it unlocks — so a key sitting unused in your inventory always has a matching door nearby.

Cross-checkedConfirmed against several independent walkthroughs of the build 1.0 (launch build, August 2026) on August 22, 2026. Codes and sequences in this game are fixed, not randomised per save. If a patch changes this, tell us on the contact page and we will re-check and re-date the page.

Every key, chapter by chapter

KeyChapterWhat it opens
Church Key1. A New DayThe church itself
Star Key1. A New DayThe church's upper-floor trident door and the churchyard outbuilding
Graveyard Key1. A New DayThe graveyard gate
ERC Activator Pen2 onwardNot a door — opens ERC supply crates
A.P.H. Key2. The Wake-Up CallPrinting house access
Staff Key2. The Wake-Up CallThe hotel Staff Room, holding three Lorelei tokens
Lorelei Keys ×32. The Wake-Up CallThe Lorelei lock into the hotel basement
Vertebral Key3. A Sight For Sore EyesAn Akeley Hospital wing door
Caduceus Key3. A Sight For Sore EyesA second hospital door, gating mask pieces
Fish Eye Key4. Time and TideA dock-area door
Snowflake Key4. Time and TideCold storage access
Sturdy Key5. Cold ComfortLate-chapter access on the way to the portal

Other things that act like keys

Several items are not called keys but behave exactly like them, and they are the ones players get stuck on:

  • ERC Activator Pen — every ERC crate needs one. No pen, no crate, no prompt.
  • Anti-Rust Acid — for corroded locks in the hospital. If a door refuses both hospital keys, acid is usually the answer.
  • Lorelei Tokens — three of them, each consumed by one chest.
  • Steel Gear, Printing Plates A–C, Leyden jars — mechanism components rather than keys, but they gate progress the same way.
  • The Prism — carried between the hospital's prism stations.

The rule for finding a key you are missing

Key locations in The Sinking City 2 are almost always in the same space as the door they open, and usually on a body. The Star Key is the template: the corpse is ten metres from the lock. If you are hunting a key, search the area around the door before you go looking across the district.

The second rule is that keys are chapter-local. Nothing from A New Day opens anything in the hotel, so an unused key at the end of a chapter means an unopened door in that chapter — and with no chapter select, that is your last warning to go back.

Keys versus codes versus symbols

If a lock shows a dial, it wants one of the five safe codes. If it shows symbols or a mechanism, it is a puzzle. If it shows nothing at all and simply says locked, it is a key — and this page is the index for those.

One exception worth flagging: ERC crates show a distinct prompt and are neither a code nor a puzzle. They are the single most common "why will this not open" question in the game's first week.

If a key will not work on a door

  • Wrong door, right key. Hospital doors in particular look identical; the Vertebral and Caduceus doors are in different wings.
  • The lock is corroded. Use Anti-Rust Acid.
  • It is a crate, not a door. Check whether the prompt mentions an activator pen.
  • You are in the wrong chapter. Keys do not carry forward.

The Sinking City 2 FAQ

How many keys are in The Sinking City 2?

We have logged twelve named key items across the five chapters, plus several components — the ERC Activator Pen, Anti-Rust Acid, Lorelei tokens and the Prism — that gate progress in the same way.

Where is the Staff Key?

In the Devil's Reef Hotel during The Wake-Up Call. It opens the second-floor Staff Room, which holds the three Lorelei tokens.

Why will my ERC crate not open with a key?

Because crates do not take keys. They need an ERC Activator Pen, found elsewhere on the same level.

Sources

Every fact on this page was checked against first-party material on August 22, 2026. Solutions were cross-checked against the build 1.0 (launch build).

Last verified · TSC2 Wiki