Hi would you mind explaining exactly how this mononoke mechanic works so I can shamelessly steal it for my own game?
Hello!
Sure thing! The idea is that the character owns an object that grants them power over/against the Yokai. In Mononoke it is a special sword that allows the Medicine Seller to change form, but to keep things simpler it only translates to a bonus. For Yokai Hunter Society as chose the Mask instead (if they lose the mask or it is shattered, they lose the bonus).
How it works :
Each Yokai has a three fundamentals that, when uncovered by the characters, each grant a stackable +1 to rolls made against the Yokai :
1. Katachi physical shape : The type of Yokai they are, like a Kappa, Bakeneko, Hannya etc.
2. Makoto their Origin, why they exist or brought them here. Do they exist due to a tragedy of sorts? Where they summoned by evil men? Did the stench of the many battlefield birthed by the Meiji restoration attract them?
3. Kotowari their reasoning or impulse. Sometimes the Kotowari is informed by the Katachi, but it is not always the case. A wronged ghost might be seeking vengeance against Ex-Samurai specifically, a Bakeneko against a group of people who wronged their owner, a Kappa just wants yummy buttholes.
-When I build a scenario, I write down broad "clues" that inform each of the three fundamentals.
-I track how close they are from the full story with a clock, one for each of the fundamentals. Normally those are 4-ticks clocks, exactly like in blades in the dark.
-When the players discover/encounter information relevant to a fundamental, I tick it once or twice (sometimes even straight-up filling the clock in the case of the Katachi : if they meet a Kappa face to face, it is pretty much all the information they needed hahaha).
When any one is filled, then they are given a +1 bonus.
-In-game there are also Kanji (one for each of the fundamental) engraved behind the mask. They emit a mysterious glow that only them can see when clues are nearby (they still have to plan and make the right decisions to acquire them).
I run games for mentally-drained folks that still want a mystery so it has served me well so far hahaha.