On this page of the guide to Monster Hunter Rise you will learn how to sharpen the weapon and where to find and how to use the whetstone.
Weapon sharpness gauge-where is it?
After each blow, the level of your weapon's sharpness will begin to decrease. The weapon status gauge, located in the upper left corner of the screen, is divided into several colors. When the sharpness drops to Orange, your weapon will occasionally begin to slide on the monster, instead of inflicting damage.
A better weapon has a larger sharpness gauge. The blacksmith in the village will forge for you a weapon that will last longer when fighting the enemy.
Whetstone - how to find it?
Whetstone is the basic equipment of your character and is used to sharpen all types of weapons. This item will never be destroyed and is assigned to the default shortcuts, along with Kunai blades and food rations.
In the lower right corner of the screen you can see the objects bar. Press L to select a whetstone, and use Y or A to move around the object bar.
Whetstone - how to use it?
It will take a few seconds to sharpen the weapon with a whetstone. During this time, you are vulnerable to enemy attacks. Move to a safe distance and press Y to use the object. If you start using the whetstone at the wrong time, press B to dodge and exit the animation, but your weapon will not be sharpened.
The best way to safely sharpen a weapon is to use a whetstone while riding. Press A to mount your companion, then sprinting (holding r) use the whetstone.