Stretch

This is how you take a successful formula, improve it and fill it with tons of content. Plus it has that special Nintendo polish other developers fail to deliver with their bug-ridden game releases. Should be in consideration for game of the year together with Bayonetta 2. It doesn't get much closer to perfect "fun" than this.

You need to spend a fair amount of time to learn the game. The lack of a tutorial is sad, but the manual is good. If you manage to "survive" the first couple of hours figuring things out, you're in for a treat with great strategic depth. It's one of those Paradox gems which will get even better with time thanks to its player community and lots of patches.