It allows the injection of a payload that lets one run unsigned code on the Wii U, achieved via a Raspberry Pi Pico. The Pico is ultimately used to boot off an SD card running a recovery program ...

an external SD card slot, and a lot of hard work on the power supply circuit — although [banjokazooie] reports that the hardest part was cutting to size a custom PCB to mount it all on.

For Wii U, Pretendo – a fan group which has previously ... you’ll still have to go down the homebrew route by downloading a patch to an SD card. There’s arguably more unique online offerings ...