THE BACYellow Threshold

Cinevva's analyzer read this game's design doc and its source, then wrote the brief below. "Make your own" hands it to the game creator as your opening message, so you start from a real spec rather than a one-line idea.

Create a 3D first-person Backrooms-style horror exploration game titled “THE BACYellow Threshold” (the in-game start heading can read “YELLOW THRESHOLD”). The player begins inside a fixed grid maze of fluorescent yellow office corridors with stained mustard/brown carpet, yellow walls, drop-ceiling tiles, dirty baseboards, occasional dark carpet stains, fog, and sickly warm yellow lighting. Use a pointer-lock first-person camera with mouse look, a small circular crosshair, and collision against the maze walls and closed doors. The scene should feel dim and oppressive: fluorescent tubes buzz overhead, lights flicker procedurally (some fixtures are unreliable), the atmosphere is dark brown/yellow with subtle fog, and footsteps sound on carpet. Include simple office clutter such as tables, chairs, and cardboard boxes placed around the corridors, using low-poly/CC0-style office assets where available.

Core objective and progression: explore the maze and collect exactly three glowing yellow keycards, restore power at a wall-mounted breaker panel after all three cards are collected, then reach and interact with the marked exit door. The exit is a dark door with a yellow rectangular marker/sign. The breaker initially cannot be used and displays that all three keycards are required. There are several usable doors in the maze: ordinary doors can be opened with E, while one exit-hall door is power-locked/jammed until the breaker is restored. Closed doors block movement and open doors stop blocking the relevant maze cell. Place the three keycards in separated parts of the maze, and place a note in one corridor that reads: “NOTE: The buzzing stops before it runs. Sprinting carries through these walls.”

Controls: WASD or arrow keys move, mouse looks after pointer lock, Shift sprints, and E interacts with the object centered in view and within roughly 2.6 world units. Walking speed is about 3.25 and sprint speed about 6.3. Sprinting consumes a stamina resource quickly and stamina regenerates while not sprinting; footsteps become faster and louder during a sprint. Show interaction prompts near the center of the screen, including “Press E to take keycard,” “Press E to read note,” “Press E to restore power,” door prompts, and context-sensitive exit requirements.

Add a patrolling hostile entity in the maze, starting in the corridors and following a patrol route. It should be represented by an animated ribcage/zombie-like GLB monster when available, with a dark capsule-like fallback and a small glowing yellow eye if the asset fails. It walks while patrolling and runs while chasing. The entity detects the player when it has line of sight within about 18 units and is facing the player, or when the player sprints nearby (within about 19 units, with a loose line-of-sight/nearby check). On detection it pursues the player’s last known position, makes louder/faster distant thuds, and can catch the player at close range. It should collide with maze walls and closed doors. Do not add weapons or combat: avoidance and navigation are the only defenses.

HUD and presentation: use a monochrome/retro terminal style similar to Share Tech Mono, pale yellow text, subtle glow and translucent dark panels. At the upper left show “KEYCARDS 0/3,” “POWER OFF” or “ON,” a STAMINA horizontal meter, and a SANITY horizontal meter. Keep a centered crosshair and show context prompts around the center. Show temporary narrative/status messages near the lower center. Include a start overlay covering the scene with a dark radial yellow-black background, thin pale border, the heading “YELLOW THRESHOLD,” explanatory text saying the player fell into fluorescent corridors and must collect 3 keycards, restore power, and find the marked exit while the thing sees light and hears sprinting, plus a “Click to enter” button. Starting the game hides the overlay, requests pointer lock, initializes audio, and displays a brief message that the carpet is damp and something is already walking.

Sanity rules: sanity starts at 100, drains in dark areas after approximately 1.4 seconds below the local-light threshold, drains faster when the entity is nearby, and drains further while the entity is actively chasing close to the player. Sanity slowly recovers in strong light when the entity is not close. Tint the sanity meter dark red when low and add an increasingly strong red vignette around the screen as sanity falls. Reaching zero ends the run. Stamina starts at 100, appears yellow normally and red when low. Power restoration makes the corridor lighting brighter and changes the power HUD to ON, while the flickering fluorescent ambience, buzzing oscillator, carpet footsteps, item beeps, door sounds, and entity thuds reinforce the horror mood.

Win only when the player has all 3 keycards, has restored power, and presses E while looking at the marked exit. Show an end overlay titled “ESCAPED” with text explaining that a real door was found and closed before the entity reached it. Lose if the entity catches the player or sanity reaches zero; show an end overlay titled “LOST” with an appropriate message such as being caught in the yellow halls or having thoughts flatten into the fluorescent buzz. Include a Restart run button that reloads/resets the game. Keep the overall art style low-poly, moody, yellow/brown, fluorescent, liminal, and claustrophobic, with no extra gameplay systems beyond exploration, interaction, stealth/avoidance, stamina, sanity, and the stated escape sequence.