Unreasonable hostility aside, the guy below me is kinda right. This is a fantasized version of the Sengoku period, but this isn't a Souls setting either; it's set in a fictionalized version of the real world, so it has to make sense in a real way to some extent. Souls of the dead in the form of paper being the sole cost of your gadgets & skills is pretty lazy game design-wise and doesn't really make sense in a A=>B manner of speaking. How does soul paper turn into a metal shuriken? It kinda makes sense for the Flame Vent and a few others, but why do you need them to use a physical retractible axe or spear that's attached to your arm? Spirit Emblems fit in the story thematically, but they haven't really been implemented logically as a mechanic. Though it wasn't a focus because it was mostly hidden, Bloodborne did this better with 'Story in Stats', such as Eileen possibly being from Cainhurst due to her defense values making sense. But I digress, ninjutsu hasn't really been implemented well either, since it feels like an afterthought and you can go without it 99% of the time. Prosthetic tools should really have their own ammo or usage count, with a tool that allows you to replenish them after a channel time and cost spirit emblems. Also it would be better if spirit emblems were the cost for everything else; namely combat arts, ninjutsu, and item tools/infinite consumables. There should have been more ninjutsu than just three, and not have them constrained to deathblows. Finger Whistle, Divine Abduction and Mist Raven definitely should have been ninjutsu. So to let players play around some more, each spirit emblem upgrade should grant three instead of one, increasing the cap to 30. To offset this, actions that cost spirit emblems would have incrementing cost that increases with repetitive use. For example, say Whirlwind Slash costs 1 SP. If you use it again immediately after or use any other action that cost SP (Like I mentioned in the Combat Arts page[27 Jul 2019 04:58] that we should be allowed 2 combat arts instead of 1), the cost would add to 2 and so on. There would also be skills that cost 0 or even -1, meaning they don't cost SP on the 1st and 2nd casts. Each cost stack would last 7 seconds which can be shortened by learning a passive skill. Also to balance this stacking cost and fix the mechanic in general, you wouldn't buy spirit emblems anymore (really gold for souls from a statue? It makes sense to learn skills, pray and confront memories, and even cure dragonrot, which is mystical in a sense, but how does a statue convert sen into soul paper?); instead you have a small chance of earning a spirit emblem with each perfect deflect, which encourages gitting gud in Sekiro. Also, amount of sen dropped doesn't increase with each NG. Really, it trivializes so many things that a lot of items lose their worth. Not to mention, the only tool that uses sen is kinda pointless.