small errors, or things that aren't in AC, but should be

[Goat]

I think the concept behind the parry blade's usage limit is based on how strong the impact it creates on the target, and the impact also causes the blade to wear down/deteriorate/break. So the stronger the impact, the less usage it gets.
Thats why Rasetsu has a usage limit of 20 but can only has 2000- on damage, while Nioh only has a usage limit of 4 but has 4000+ on damage.

If what im saying is correct, why does the usage limit go down even if you "miss" hitting the target.

Maybe the parry blades in ac are like the one Alteisen uses, which is driven by explosives.

Haha. This reminds me of Scopedogs. I can see shells coming out of the arm but all that they do is to freaking punch.

Maybe the pilebunkers get wasted even if you miss your target because explosives tend to explode after releasing the spike itself, and will be discarded then. I think there's always a spark in the parry blades when you try using them.