Did you use the theme?
Unlucky XIII: you’re a guest at Hotel Tredecim (“thirteen” in Latin), and your room is on the 13th floor, the floor hotels skip. The lift’s indicator goes I–XII, then XIV. The key rack has 13 hooks but only 12 keys. You have to get through 12 corridors in a row without a mistake to reach Floor XIII. There are exactly 13 omens to find, and each is a bad-luck superstition or something unsettling: a black cat crossing your path, a ladder, a broken mirror, an open umbrella indoors, a fallen horseshoe, Room 13, a backward clock, and more.

Liminal horror: the whole game is one empty, humming hotel corridor that keeps repeating. Same carpet, same doors, same lights, almost. It’s a spot-the-difference loop: if anything is wrong, turn back; if nothing is, keep walking. Each floor the lights get dimmer and sicklier and the fog thicker.

What tools did you use?
Engine: Unity 6 (C#), exported to WebGL
AI: Claude Code (Anthropic) co-wrote the code with me. I directed the design, playtested in Unity, and asked for changes.
Art: no asset packs. The hotel is built from Unity primitives in code. The cat and the bellhop are procedural meshes generated by a Python script (numpy) and baked into the game. The portrait and the cover art were painted procedurally with Python and Pillow.
Audio: every sound is synthesised in code at startup, including the fluorescent hum, footsteps, the door creak, the lift ding and the jump scare.
Text: the built-in Unity font, plus Cinzel for the cover art.

Anything to say?
First time making a game this fast. I joined with about 13 hours left and wanted to see how far I could get by pairing with an AI coding tool in Unity. The interesting part was directing it like a team: describing what felt wrong (“the cat looks like a walking blob”) and iterating until it felt right. Headphones recommended. Tell me how many omens you found!