Players need to collect different materials such as Sharp Scales in Wild Hearts to upgrade their weapons and armor, which they can get from the smaller Kemono creatures found around the world. Once Chapter 2 of the main story has been completed, players have the chance to improve items with gathered resources like Sharp Scales. Although not as easy to find as Demon Rock, it is also not as difficult as some boss-exclusive items, Sharp Scales only provide a small challenge for players.

https://screenrant.com/sharp-scale-drop-locations-wild-hearts/