*What I Built
GhOStly (Ghost + OS) is a horror mini-game where your own desktop becomes the haunted level.
A tiny ghost floats on top of your screen with one button: START. Before pressing it, you can drag the ghost onto any app, window or folder you like. The moment you press START, the game takes a screenshot of your screen, finds every icon and every piece of text, and turns each one into a monster with glowing eyes and teeth. Then a little exorcist hero appears in front of you. You control him with the keyboard, aim a magic lantern with the mouse, and purify every monster. A purified monster turns back into a normal icon.

How I interpreted the theme: "Ghost in the Machine", taken literally. The ghost lives inside your own computer (inside the OS), and the haunted house is the screen you use every day. The twist at the end goes one step further: the real ghost might not be in the machine at all.

Code

still4shrishti / ghOStly

👻 ghOStly

An eerie and innovative 2D Action-Shooter Game where your own desktop environment turns against you! Upon launch, the game captures a snapshot of your screen and mutates your apps, folders, and text into hostile anomalies.

Will you exorcise the ghosts haunting your desktop, or will you succumb to the monster within?

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🔥 Features

• Desktop Camouflage Mechanic: The game dynamically crops your real desktop icons and turns them into floating, twitching entities.
• The Little Exorcist (Hero): Control a robed wizard holding a glowing lantern that illuminates the dark voids left by your missing desktop items.
• Intense Final Boss Fight: Once the minor entities are cleared, the desktop fragments converge into the center to assemble "The Desktop Beast"—a towering humanoid titan plated with your own icons.
• Cinematic Horror Twist: A scripted atmospheric ending sequence that shifts the focus directly onto the player.
• Immersive Visuals: Features dynamic lighting glows, active…

View on GitHub

How I Built It
Python + pygame for the game loop, graphics, hero animation, hearts and sound
mss to capture the screenshot
OpenCV + NumPy to find icon and text shaped blobs (edge detection and dilation), which are then cut out and turned into monsters
PyInstaller to package the game as a Windows .exe
I used an AI coding assistant (Claude) to help write and debug parts of the code.
Open-source AI part:

Why Does Open Innovation Matter?
This game only exists because of open-source tools. pygame, OpenCV, mss and NumPy are free, inspectable and well documented, so a small team could build a full game in a hackathon.

It also matters for privacy. This game reads your real screen, which can contain private things. Because everything runs locally on your own machine, the screenshot stays in memory and is never uploaded anywhere. A closed cloud API would have meant sending pictures of your desktop to someone else's server.
The Spirit of It
The part I care about most is the ending. After you purify the last monster, the game asks: "How will you kill the monster inside you?" The screen turns dark, the hero walks to the middle, looks straight at you, his eyes turn red, and the screen goes black. Then the program closes and your desktop returns to normal, as if nothing happened.
I wanted the scariest place in the game to be somewhere you already trust: your own screen.