Personally getting slightly annoyed at all the people that are completely misinterpreting what this game is. No, it's not Dark Souls. No, it's not Devil May Cry. It's Ni-Oh.
The closest thing I can think of in terms of game description is that it's Ninja Gaiden x Dark Souls. Anyone that has played Ninja Gaiden is well aware of how brutally punishing those games are and anyone that has played a Souls game knows how mechanically dense and trial-by-fire those games are.
I'm not disagreeing that the game has issues at all. The lock-on system is garbage. The game looks like ass and yes, the enemies probably have slightly too much HP or too much damage in the current state of the game, though it's my opinion that only one of these needs to be lowered, whether it's the HP to make battles for quick and decisive or the damage to make it closer to Dark Souls in that you can take 5 or so hits before dying instead of 2.
The systems are pretty solid though. The three stances give you options between speed (low), defence (medium) and offense (high) and an entire unique moveset with more attacks, parries, special moves etc. being added as your character levels up.
The Ki system is also great. Yeah, it sucks when you run out of Ki and your character stands there panting before likely getting knocked on his ass if not outright killed, but that should never be happening. The Ki charge mechanic is really simple even if the game doesn't do a good job of explaining it. Any time you attack, the red parts of the ki bar that you expended in the attack string start refilling with white. Tapping R1 refills that bar to that point. The longer you leave it after an attack string, the more Ki you regenerate, but also the more open you leave yourself to attack, and if you don't hit R1 before you perform your next Ki-expending action, all of that Ki is lost and the Ki that would normally be expended is also spent.
The thing is, you can use this mechanic even when you are out of Ki after an attack string to restore a minuscule amount, which can then be used for something like an emergency dodge roll away. After that you're screwed, since you can't Ki charge after a dodge roll, but you probably were anyway if you were in that bad a situation.
The spear even gains a move so if you Ki charge after a certain period of regeneration, it triggers a powerful and quick interruptive spin while restoring your Ki meaning that you lose a lot of that vulnerability.