Spooky Keychain Arcade

Meet theSpooky Keychain Arcade: A Cute Halloween 2-in-1 Gaming Console!

What if your Halloween accessories weren't just decorations, but fully playable retro gaming machines?

The Keychain Arcade is a wearable, pocket-sized gaming console cleverly disguised inside a cute, 3D-printed Halloween ghost. Designed to clip seamlessly onto your backpack, keychain, or even double as a hair clip, this tiny gadget brings nostalgic 8-bit arcade action wherever you go.

Powered by the miniature Seeed Studio XIAO nRF52840 microcontroller and a crisp 0.96" IPS ST7789 color display, this little ghost packs a serious punch. Utilizing custom double-buffered graphics, it delivers a silky-smooth 60 frames per second with hand-crafted pixel art and zero screen tearing.

Inside, players can toggle between two complete Halloween-themed games:

1. Gost Run: An endless side-scrolling runner set against an 80-row full-screen sunset sky. Guide your cute animated ghost over carved Jack-o'-Lanterns, spooky tombstones, and swooping bats with responsive physics jumping.
2. Ghost Pong: A fast-paced duel against a reactive CPU in a dark, atmospheric graveyard. Deflect a tumbling 8×8 carved pumpkin ball using miniature bone paddles!

With internal non-volatile flash storage (LittleFS) that saves your high scores and win streaks even when powered off, and built-in USB-C rechargeable LiPo battery monitoring, the Keychain Arcade is the ultimate blend of 3D printing, embedded electronics, and Halloween fun.

1. XIAO 0.96'' IPS Display(nRF52840)
2. 3.7V 200mAh LiPo battery 501530P
3. Black and white PLA+

The core component of this project is the new 0.96" IPS Display module with XIAO nRF52840 Plus from Seeed Studio. It is the most compact member of the XIAO IPS Display series. Built on a 17.8 mm-wide board, it integrates a 0.96-inch IPS display, PDM digital microphone, 6-axis IMU, two user buttons, a battery connector, and the pre-soldered XIAO nRF52840 Plus.

It is designed for tiny BLE status displays, smart badges, wearable notifiers, motion controllers, digital pets, and other battery-powered devices where size matters.

The enclosure for this project uses a simple three-part design: a front part, a back part, and buttons. For the front part, I used a multicolor design to get the ghost printed quickly with the black-and-white PLA+ combination. The buttons are also 3D printed in black. The STL files and STEP file for this project can be attached below.

The first part of the assembly is soldering the battery to the battery terminals of the display module.

1. Place 2 switch caps on the front body
2. Place the display module into the enclosure
3. Close the back cap, which snaps into place

Find the code HalloweenGhostGame.ino.ino file is attached below, along with some.h files. Open the code in the Arduino IDE and flash it. Use the Seeed Studio nRF52840 Plus in the board selection. In the GOST running code, you can change this parameter as you like to alter the gameplay.

Find the code here https://github.com/gokuxmaker/-Keychain-Arcade

Guide your cute animated ghost over carved Jack-o'-Lanterns, spooky tombstones, and swooping bats. Your running speed will increase as your score increases.

Ghost Pong is a simple game, exactly like ping pong. Here, you need to play against your own microcontroller, which is quite a big challenge. The pong slabs are bone-shaped, and you are bouncing around the Halloween pumpkin.

Now it's time to put this on your key chain. Now that’s a great time pass if you’re in a situation like waiting for someone. But we only have 2 games, but I will have more and update this device soon. Hope you like this project. Happy making.