@Pluton9 Thank you for the response.
Indeed, there are items capable of repelling monsters, like the 'Morbul,' so far the only one with this effect (I think), although it has disadvantages, such as its odor and temporary effectiveness. If the item's effect dissipates at an inopportune moment, the consequences can be severe, as we have already seen.
Regarding the repellent effect area of the scale, it should be substantial, especially for lower-level monsters, which typically have less intelligence. I imagine that even a faint aura from a level 10 monster would be enough to make them flee and keep their distance.
Smarter monsters wouldn't flee but would choose to maintain a safe distance. This strategy would be effective as long as adventurers were not actively pursuing the monsters because, if the monsters realized it wasn't a level 10 monster but just a part, greed could prevail. This could result in a group of monsters eager to devour the scale, thus increasing their own strength, as you mentioned.
Considering the utility of the scale, I thought of using it as a safeguard during camps. Placing it in the center of the camp would allow adventurers to sleep peacefully, without worrying about surprise night attacks. Of course, it would still be necessary to conduct nighttime patrols to ensure total security, but the scale would serve as an additional layer of protection.