Do you want to unlock all characters/karts/trophies and so on? then it is time for you to try the Mario Kart 8 game trainer on Wii U.
Just follow this simple tutorial below and you will unlock everything in no time.
Required file :
MK8 Trainer : http://tinyium.com/3BNM
Advanced IP Scanner : https://www.advanced-ip-scanner.com/
Thanks to Mega-Mew from Gbatemp : https://gbatemp.net/threads/release-yet-another-mario-kart-8-trainer.468954/