This are infos we have:
It is a ‘port’ but more of a complete rework for the Wii U: a bit like the work we did on Deus Ex: Human Revolution – Director’s Cut.
I can’t say what the title is but it is very exciting and is for an absolute top notch publisher.
This game will be credited Tantalus … it’s not an MA / 18 or ‘hard core’ game which ME-3 and DX:HR are.
I understand they working on port of game that was already is launched and its not M rated.
We’re doing that. It hasn’t been announced, but it will be soon. And can I just further add to the mystique and say that it’s big. It’s the biggest thing we’ve ever done. And it’ll come out this year, and I hope it won’t disappoint.
http://nintendoeverything.com/?s=+Tantalus
So if look this infos and dates of them, they began to work on game in January 2014, it's game that is released before 2014. and its not M rated.
Edit. Maybe Nintendo gave them to port some GC game. It is a ‘port’ but more of a complete rework for the Wii U, an absolute top notch publisher, not M rated or hardcore, biggest thing they ever done and it’ll come out this year.
