This tutorial is based on sections of tutorials listed below. https://sites.google.com/site/completesg/backup-launchers/gamecube/cmios https://gbatemp.net/threads/gameboy-advance-original-sp-micro-as-gamecube-controller-for-wii.435282/ https://sdremix.com/installation/gamecube-installation/running-gcn-homebrew/ This requires a Wii U + Gamecube Adapter, and a Wii with Gamecube Ports or a Gamecube capable of running Homebrew! You'll need to follow these steps each time you want to play using the GBA! 1. Extract the ZIP located at the bottom of this post to the root of your SD Card. Wii Steps 2. Obtain the latest MIOS version using NUS Downloader (the steps are located at the top of the first link). 3. Place the MIOS wad renamed to "RVL-mios-v10.wad" on the root of the SD Card. 4. Remove the SD Card from your computer, and place it into the Wii. 5. Go to Homebrew Channel and launch "Installer for WiiGator's cMIOS." 6. Set the install IOS to IOS 249 and Press A. 7. Press the button it tells you when it pops up. 8. Press the A button for the remaining menus. 9. Launch WiiXplorer and navigate to the SD Card. 10. Click on gbi.dol and select GC Homebrew. 11. Connect your GBA to any port using the Link Cable. 12. Turn the GBA on without a Game in the slot, and wait for the screen to turn blank. 13. Press buttons on the DPad, If the values on the screen change, then that means it worked. If the values don't change, try plugging it into another port. Gamecube Steps (Untested) 2. Enter Homebrew through your preferred method. 3. Launch gbi.dol. 4. Connect your GBA to any port using the Link Cable. 5. Turn the GBA on without a Game in the slot, and wait for the screen to turn blank. 6. Press buttons on the DPad, If the values on the screen change, then that means it worked. If the values don't change, try plugging it into another port. The GBA should work if plugged into the GC adapter for a game like Super Smash Bros. However, you won't be able to control the characters as the DPad is mapped to the normal DPad. Thankfully there's HID to VPAD! https://github.com/Maschell/hid_to_vpad/releases (or the Wii U Plugin System by Maschell https://github.com/Maschell/WiiUPluginSystem/releases) I've included an ini file called "GBA Smash.ini" which I have tested with Super Smash Bros. It works somewhat well. Wii U Steps 1. Take the SD Card out of your Wii/Gamecube and plug it into your computer. 2. Add HID to VPAD to your SD Card. 3. Remove the SD Card from your computer. 4. Plug the SD Card into your Wii U. 5. Launch Homebrew through your preferred method 6. Run HID to VPAD. 7. Assign the GBA to a controller slot, and press the Plus/Start button on your Wii U Gamepad/Wiimote. 8. Start the game of your choosing and play with a GBA!