Would "PS1 - Expert Trial Mode" be an interesting category?

Loss%

Run finishes when you arrange Loss in your inventory.

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Example:

FAS              First Aid Box Backdoor Key Reloading Tool

I call this the "Fragile Knife": Knife only, but you can only equip it during CT nemesis and acid nemesis. You must unequip it whenever you are not in these encounters. Bonus points for swinging it the exact required amount of times, which, if i'm not mistaken, is 85 slashes.