Because Haxchi let you play as the own Haxchi it's a
Region Free CFW.
If you have an
US WiiU Console and you want run a Game from different Region, you can by default with the Haxchi, but if the game it has more than one language inside the Game coding, as example:
EU Game with 5 EU Languages the CFW it's able to run it but will run the English as default, and there are the Games that you cannot change the languages into the Menu Game; because the Software House it let change it automatically on base of your Console Region (could be that even don't run at all)....Here comes Spiik, Spiik "fake temporary the System" (without to change any System Language) to let think to the game to run in, as an example: Spenish Console and the game by default will change in Spenish.....
To run Spiik if you need it, you have to go here:
https://github.com/marco-calautti/spiik/releases/tag/v0.1b
Download it, Copy the .elf file and paste into SD:/wiiu/apps/ (here create a folder called Spiik and paste into it), then you can use Spiik before run any particular Game, and this must to do in each reboot of the system, because after reboot (as normal as it is) the RAM will be wiped and the functionality of the app must to be run as any other Homebrew App again (after rebooting the system, if you need).