Snow Fox Brush

"United, they exacted revenge and erased all grudges." The lingering resentment of the deceased white fox transformed through her fur into this brush. With it, you can take on her form and fulfill her final wish.

Used to turn the Destined One into a fox. While in a fox form, you will need to find a specific monk, Non-Void, in New Thunderclap Temple's Temple Entrance. Being in a fox form will trigger cutscene and a boss fight.

From Valley of Ecstasy's Forest of Felicity, just strait ahead there will be a dead body leaning to wooden beams. Interact with it to obtain it.