Apprentice's Whetstone

One of the more common relics of the Dwarven empire, these whetstones were created in vast numbers and issued to almost every dwarf that served as a soldier, guard or hunter. One of the first techniques to be taught to a young stonesmith was called hragh-zuk, which roughly translates as the "renewing". In some parts of the North Coast, in areas formerly inhabited by dwarfs, they are so plentiful that they are used as part of the local currency among local Goliath herds.

This magical whetstone has 3 charges. As an action, you expend a charge to sharpen one weapon that does slashing or piercing damage. Once this is done, you gain a temporary +1 bonus to attack and damage rolls made with that weapon. The effect lasts until you miss an attack roll with that weapon.

Every time the whetstone is used, you must roll a D20. On a roll of 1 or 2, the whetstone cracks and becomes useless, and is destroyed. On a 20, the bonus given by the whetstone for that use becomes +2.