A game with a nice gameplay loop, parrying and retaliating is rewarding and puts your mind on focus. The ninjas, they are well telegraphed and require knowing their timingin order to defeat, the only fault here is that they can dash from outside of view and net you a hit. The arrows, oh the arrows, how much i hate them, they come out of nowhere at a lighting speed and the timing tends to synchronize with the attack of the other enemies which means you have to dodge instead of parrying and as such loose the tempo of it and now you have to deal with 2 ninjas and the fast arrow that is peaking around the corner, after the game spawns 3 arrows the game becomes impossible.
Theme, the one slash is coupled with the parry creating a nice cycle of parry-attack-parry-attack, not only is the theme implemented but its really solid.
Originality, similar to the one shot kind of game but the necesity to parry and relentlesness of the enemies puts the player into a more aggresive mindset.
Great game to spend some time with, go play another thing and then get hooked back again to play some more. (But seriously fix those arrows.)