So, I'm really, really enjoying this game.
Its an indie title so its not getting that much exposure, but I'd highly recommend it to anyone that wants a new MetroidVania for Wii U. It's a big game featuring full voice acting, 200 rooms to explore, 100 weapons, 3 different endings, difficulty levels etc, etc...
There's a trailer here: https://www.youtube.com/watch?v=DQrVNPPjtuE
And here's a review: http://www.nintendolife.com/reviews/wiiu-eshop/unepic