This one is easy to build RetroPie mini machine.

List: Raspberry Pi Zero x 1 (any supply)

Battery: I use Drone Spare lipo Battery with 1,200 mAh https://www.aliexpress.com/item/6Pcs-Set-Original-3-7v-1200mAh-with-Charger-Units-for-SYMA-X5-X5C-X5SC-X5SH-X5SW/32847528965.html or (I think this one also OK) https://www.aliexpress.com/item/Portable-3-7V-1000mAh-Li-polymer-Battery-102050-Cell-Li-Po-Rechargeable-Batteries-For-MP3-MP4/32915309053.html

Raspberry Pi Game Zero W + 1.54 inch mini LCD touchscreen: https://www.aliexpress.com/item/Raspberry-Pi-Game-zero-W-2B-3B-1-54inch-mini-LCD-touchscreen/32970035492.html

Speaker: I use AIYIMA Mini audio portable Speakers 0.25W 8Ohm 21mm https://www.aliexpress.com/item/20pcs-0-25W-8Ohm-Speaker-External-Magnetic-Speaker-Dia-27mm-for-Toy-Aduio-DIY-free-shipping/32579182632.html

PAM8403: (or any amp you like) https://www.aliexpress.com/item/PAM8403-Super-mini-digital-amplifier-board-2-3W-Class-D-digital-amplifier-board-efficient-2-5/32725185408.html

1A Lipo Battery Charging Board: Actually I do not remember which one I use but it look like this https://www.aliexpress.com/item/Nartor-10pcs-or-5pcs-TP4056-1A-Lipo-Battery-Charging-Board-Charger-Module-Lithium-battery-DIY-Micro/32832474188.html

*** If you purchase part from Aliexpress "avoid" this shop (ANA FANG)

https://www.aliexpress.com/store/912623196

This is SCAM shop. They send empty package with no item. The trick they use is deliver with register mail, while you get item and open there is empty nothing in the mail. The part might cheap and you can let it go but it waste time to wait for new order.

How to assemble: Just put it in the place that show in pictures. Due to this one I got 2 1.54 inch HAT so I will make a tutorial soon.

Actually I should upload my Retropie iso but I have problems with share space online if I get the cloud or something like that I will upload my clean Retropie ISO if able. (the main reason that i rework on Retropie iso for this HAT is the supply one really slow and not suit for game device)

The Thing preview (In Thai language): https://www.youtube.com/watch?v=i8zQhowIcmo

*** WARNING *** buy product from China store some part might not work please notices this before purchase.