Well... this is my number 1 for this jam so far. The art is cute and clear. The boss battle design is something on another level (the tension when fighting with the last boss... masterpiece). Everything is on the right place.
What is more interesting, this game trains your patience... the samurai way.
The only thing I'd improve is to made loading katana a little faster, or give some audio feedback it has just loaded.
Other than that... I LOVE THIS GAME!