Not too sure how Nintendo eShop region-ing works, as I don't own a Wii U but:
Shadow Archery is an endless arcade-style light gun shooter inspired by 8-bit games of the day, and it will be heading to the Wii U eShop on 12th April in North America (European release details are expected soon). You can play the game with either the Wii U's GamePad or a Wii Remote if you prefer, as you aim to take out the pesky Arachners and help Archer survive in the Darker Realm.
You'll be fighting against hordes of creatures using your trusty crossbow, finding power-ups to aid you in your survival against the ever spawning creatures. Your arrows are limited, however, so you'll need to make every shot count.
Amazingly, the game is set to launch for the very low sum of 'free'. Yes, for the first week of the game's release, you'll be able to download Shadow Archery for free, with the price set to rise to $0.99 / €0.99 thereafter.
It looks like a VIC-20 game