Mario Galaxy crossed with an old school shmup. Great fun in co-op.

Nano Assault Neo is definitely a different type of twin stick shooter. It's very pretty to look at, and makes use of its cell concept to make it a very interesting game. The only problem it really faces is the scoring system, while different, suffers from a steep learning curve and hinders replay ability more than it gives. Otherwise its a blast on its own and uses the Wii U features quite well.