We 3D print the Game console case and buttons, you order the electronics, and assemble! 
 
Youtube: https://youtu.be/xzfvlyLVFtw
 
This project takes the original concept of the PiGRRL and makes it more powerful, using a Raspberry Pi 2. It's about the same size but features more buttons (D-Pad, A,B,X,Y, L, R, pause and start.) and four extra buttons on the PiTFT. It's sporting a small audio amplifier and speaker, so you can enjoy the crispy sounds of 8-bit goodness. 
Easier to build!
With this update, we really wanted to make it easier to build. We've dramatically cut the build time in half by making a custom gamepad PCB. Just solder in the buttons and an IDC box header to the gamepad PCB - No more tedious button wiring!
 
Project Expectations
 
This project is geared towards beginners, but is still a big project to take on. This guide will walk you through all the necessary steps to wire, assemble and build your very first Raspberry Pi game console. It does require a good amount of soldering, wire tinning and good ol' elbow grease, but don't be discouraged! If your dedicated to take on this project, it'll only take a weekend to make.
 
Adafruit Parts
Raspberry Pi 2 or Raspbery PI 3
2.8" PiTFT Plus
PiGRRL Gamepad PCB
PowerBoost 1000c
2500mAh battery
PAM8302 2.5W Audio Amp
Mini Metal Speaker
40pin GPIO ribbon cable
Slide Switch
10x 6mm + 2x 12mm tactile buttons
1x 2by20 pin IDC box header
 
Approximatly $110 in additional parts.