The problem here (that didn't happen in Megaman) is that the currency for gadgets/prayer slips is limited, which, depending on each player mindset, may enact the opposite response of "whatever", followed by the use of sheer skill until a boss is defeated, while slips get hoarded and gadgets unused.
And yet, if you've played for a while, you'll know that the Spirit Emblems, like the Quicksilver Bullets, aren't really that limited. And Fromsoft's were quite clear about the usage of each tools, while also hiding some of its usage.
Weird how when it comes to games like this, you'll usually requires cool, useful gadgets to be limited to some extent, less we get the spam complains all over again.
Flame Vent felt really weak to me too.
It trivializes the Red Eyes encounters, alongside the Fire-upgraded version of the other prosthetics. Other than the Chained Ogres, you can encounter more of these type of enemies if you do the side contents.
Also, Flame Vent and Fire-enhanced normal attacks you can do with the help of Living Force should be OP. If we apply the logic of still taking chip damage and Burning status buildup from perfectly deflecting Fire-based attacks with your katana, then enemies should still take vitality damage from deflecting your Living Force-Flame Vent attacks. The same when using the Projected Force with the Fire Umbrella.
I also didn't really use the feather or leaf one either.
The Feather can be used to completely remove the damage from performing Lightning Reversal. But I can see why people ignore this; the damage is negligible, there's literally only 2 instances where the Lightning Reversal is ever needed (the Divine Dragon doesn't count since you don't even take damage from performing it), and between paying 2 Spirit Emblems and taking a negligible amount of damage... yeah.
You can also do this:
The Spear was another axe scenario. Great for ripping off armor and a few other practical applications. Otherwise, didn't use it.
Have you tried using it against the Headless Ape?
The Umbrella Hat things were good for when I knew what type of damage an enemy would be doing but I wasn't sure about the best way to play around it yet.
When fighting Sword Saint and Owl (both Great Shinobi and Father), you'll notice they have an attack which, when deflected, would knock Sekiro back and make you briefly lose control for a bit (though brief enough to let you ready yourself for whatever's coming next). Perfectly deflecting them with the Umbrella prevents the knockback completely, and the Projected Force allows you to immediately counter attack with decent damage to posture (and even vitality if they didn't recover on time).
I've pretty much listed all these in
my post above, but to further add to that and what Silva said that I quoted in this post: The main problem with Sekiro is content. There's not enough amount of enemy and not enough amount of different enemy type to give players a chance to really play around with the stuff they provided us with. The minibosses are not only duplicated as a more miniboss fights, some of them are even placed here and there as regular mobs. I guess this is the price they pay for clarity and more focused narrative, alongside with their mostly experimental gameplay iteration.
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