The Sinking City 2 Collectible and Secret Puzzle Guide: ERCs, NG+ Documents, and Trophies

Frogwares’ shift away from the pure detective formula of the original 2019 title toward a strict, uncompromising survival horror framework has fundamentally altered how players must approach the drowned streets of Arkham. Early reviews and video impressions have frequently compared the game’s moment-to-moment tension to modern genre staples, noting that the creeping dread is amplified by a persistent lack of ammunition and medical supplies. When every encounter with the Deep Ones or the Slither drains your meager inventory, thoroughly scavenging the environment becomes a mandatory practice rather than an optional side activity.

Based on early community reports and datamined findings, The Sinking City 2 is heavily front-loaded with cryptic combination locks, secret stashes, and obscure puzzle mechanics that hide the game’s best loot and most disturbing lore. This article compiles the community-reported solutions for the most difficult trophies, the locations of high-value supply caches, and the requirements for the elusive New Game Plus collectibles.

Emergency Relief Crates and the “Behind Every Crate Man” Trophy

Because survival is so heavily dependent on your inventory, players need to be on the constant lookout for Emergency Relief Crates (ERCs). These heavy-duty military-style chests are reportedly scattered throughout the game’s flooded ruins and contain massive windfalls of ammunition, crafting components, and restorative items.

Finding all 13 of these crates is expected to unlock the “Behind Every Crate Man” trophy. However, spotting them in the dark, waterlogged corridors is only the first step. Community discoveries indicate that these crates are electronically sealed. To crack them open, you must explore the immediate vicinity to find corresponding “ERC Activator Pens”—specialized key items required to bypass the locking mechanisms.

The crates are reportedly distributed across the campaign’s five main chapters:

• Chapter 1: 1 ERC
• Chapter 2: 3 ERCs
• Chapter 3: 3 ERCs
• Chapter 4: 3 ERCs
• Chapter 5: 3 ERCs

Since missing a single crate could jeopardize your achievement run, it is highly recommended to consult a thorough resource and inventory guide to optimize your loadout before venturing into the more dangerous, heavily submerged districts where these crates are typically hidden.

The Ex Oblivione Mode and New Game Plus Documents

Frogwares has woven substantial replay value into the game through its New Game Plus offering, which is reportedly titled the “Ex Oblivione” mode. Instead of simply scaling up enemy damage and health, this mode introduces entirely new narrative elements designed to flesh out the cosmic horror elements of the Cthulhu Mythos and provide closure on the game’s more ambiguous plot threads.

Players tackling Ex Oblivione will find eight exclusive documents scattered throughout the world. Collecting all eight is expected to unlock the “From Oblivion” trophy. These are not standard diary entries; their titles suggest heavy lore implications regarding the true nature of the flood and the entities lurking beneath it.

According to early community mapping, the documents are found in the following distribution:

• Chapter 1: 1 Document (The Son of Cthylla)
• Chapter 2: 2 Documents (The Beauty of Survival, The Mother of Invention)
• Chapter 3: 2 Documents (The View From Outside, The Pursuit of the Unknown)
• Chapter 4: 2 Documents (The Burden of Knowledge, The Joys of Discomfort)
• Chapter 5: 1 Document (The Loss of Calvin Rafferty)

The inclusion of documents like The Son of Cthylla and The Loss of Calvin Rafferty strongly implies that the second playthrough will peel back the curtain on the protagonist’s fragile mental state. Expect to face significantly tougher encounters while hunting for these papers, making careful navigation through the flooded city blocks essential.

Cracking Secret Safes and Combination Locks

Arkham is littered with combination safes, locked storage rooms, and cryptic mechanisms that guard valuable resources and unique trophies. Unlike the linear lockpicking minigames seen in other titles, The Sinking City 2 heavily utilizes its investigation board to force players into connecting logical dots.

The Damned Trophy: Salt Storage Code

While navigating The Harbor, players will reportedly encounter the Fish Market, a grotesque area filled with rotting catch and lurking aberrations. Deep within this market is the Salt Storage room, sealed by a four-button locking mechanism. Brute-forcing the lock is highly impractical. Instead, you must scour the immediate area for three specific notes: The 16 Punishments of the Sailor, Instructions to Sybil, and Warning for Sybil. By combining these clues in your mental palace, the correct sequence is revealed. Entering the code grants access to the storage room and unlocks “The Damned” trophy.

The Drowned Trophy: Ezekiel’s Safe

Also located in the Fish Market is a chained Fish Shop. You will need to have located the Bolt Cutter elsewhere in the level to snap the chains and gain entry. Inside, the environment tells a grim story—the corpse of a man named Ezekiel is found clutching a safe with a four-symbol cipher lock. To figure out the correct symbols, investigators must find two specific documents: From Ezekiel’s Wife and About Ezekiel. Connecting the tragic backstory detailed in these notes will provide the correct sequence, opening the safe and triggering “The Drowned” achievement.

The Vault Trophy: Hospital Basement Storage

The atmosphere changes drastically when you leave the docks and enter The Hospital Grounds. In the flooded, pitch-black basement of the hospital, players will find a highly secure Storage Room locked behind a traditional four-digit numerical keypad. The combination is broken into four separate pieces of evidence scattered across the medical facility: a note with the digit “3”, a letter with “1”, a note with “0”, and a memo with “8”. The order in which these digits must be inputted is not immediately obvious; you must read the context of the memos and arrange the clues in your investigation interface to deduce the correct order and unlock “The Vault” trophy.

The Red Press Achievement

This obscure puzzle revolves around a cursed printing press located in a heavily waterlogged district. To operate the machine and unlock the achievement, players must locate three specific printing plates (labeled A, B, and C). Community feedback suggests that Plate C is typically found first along the natural critical path. Plate A is reportedly located on the third floor of an apartment building situated directly east of the Printing House itself. Plate B requires further exploration of the surrounding flooded alleys. Assembling all three plates on the press completes the puzzle.

Essential Story Puzzles Highlight

While the aforementioned safes and crates are optional, The Sinking City 2 also features mandatory progression puzzles that require significant legwork and deduction.

The Strange Statue and the Heart of Ice (Chapter 4)

Chapter 4, reportedly titled Time and Tide, features a massive, multi-stage puzzle involving an Abandoned Office and a Frozen Statue located in the Fish Market’s Cold Storage. The ultimate goal is to obtain an item called the Heart of Ice.

The sequence of events is complex. Players must first acquire the Antikythera mechanism, which triggers an interactive cutscene and a subsequent nightmare sequence involving a character named Ma Fishface. Upon surviving the dream, players can retrieve the Heart of Stone and a Cryptic Riddle from a nearby safe. Returning to the Abandoned Office, you are confronted with a bizarre statue that requires you to shoot specific arms off of it to reveal the Heart of Ice. A crucial community tip for survival horror resource management: shooting the correct arms on this statue reportedly does not consume real ammunition from your inventory, so you can solve the spatial puzzle without wasting bullets before returning the Heart of Ice to the Cold Storage area.

Opening the Library Floodgate

Much earlier in the game, your boat’s passage to the Miskatonic Library Annex is obstructed by a heavy, broken floodgate. The mechanism is entirely dead, requiring players to disembark and explore the surrounding buildings on foot. You must locate the main fuse box near a Safe Room and find the Gate Switchboard clue in a building directly across from the gate itself. To restore power, you are required to plunge into the dark, submerged lower levels of the adjacent buildings to scavenge three missing Electrical Fuses. Only after successfully routing the power can you pull the switch, lower the water levels, and safely navigate your boat toward the Annex.

As more players gain access to the drowned streets of Arkham, further secrets, optimal puzzle routes, and hidden Cthulhu Mythos references are expected to surface. Until then, managing your ammunition, carefully connecting clues on your investigation board, and thoroughly checking every shadow for Emergency Relief Crates remains your best chance at surviving the ordeal.