The Silent Expedition Echo Protocol

The Silent Expedition Echo Protocol is a co-op first-person horror game for 1–4 players, set in endless liminal backrooms where reality feels wrong. You wake in a cold, humming corridor with no idea how you got there. Your only real tools are a flashlight, almond water and your teammates; you cannot fight the entities that roam the halls.

Survive the entities

You stay alive by listening carefully, moving slowly, closing doors and breaking line of sight. Several kinds of entities roam the backrooms, each with distinct behaviour and sound design. Some hunt by sound, reacting to footsteps, doors and voice chat; some stalk from a distance and wear down your sanity; others appear unexpectedly and turn safe spaces into death traps. None can be killed, so you must hide, outsmart them or escape.

Almond water restores both health and sanity. Running out gradually drives you insane and changes how the world looks and feels. The game includes sudden noises, blood, dead bodies and disturbing imagery.

Explore the backrooms

Interconnected levels include offices, storage areas, maintenance tunnels and abstract spaces that should not exist. Each level has its own layout style, lighting and soundscape. Keys, codes, mechanical parts and almond water can appear in different preset locations on each run, while dead ends, fake exits and looping corridors disrupt your sense of direction.

You solve small environmental puzzles and use clues to unlock areas and shortcuts, as well as activate machinery. As you push deeper into new levels, sanity drains faster and hiding places become rarer. You may eventually escape, or die and try again with a slightly different layout and item placement.

Co-op for four players

The game is designed primarily for online co-op, with 1–4 players in PvE, but you can also play solo for a harder, lonelier experience. Proximity voice chat lets you whisper, warn teammates and coordinate—or panic together when something stirs in the dark. You can read notes aloud, call out codes, mark doors and warn others when you spot movement.

Splitting up can speed up searches, while staying together is safer but makes progress slower. When a teammate dies, the survivors must decide whether to push on or try to bring them back.

Search and escape

A run begins with a flashlight and a search for keys, codes, fuses, mechanical parts and almond water. You solve environmental puzzles, avoid or escape entities that patrol and react to noise, then venture into deeper levels in search of a way out.