Razorcap Mushroom

The Razorcap Mushroom is a curious and eerie fungal growth with a cap resembling a serrated blade. Its cap is sharp, knife-like, and metallic gray, while its stem is dark and studded with needle-like protrusions. When touched, it feels cold and sharp to the touch.
When the Razorcap Mushroom is harvested and properly prepared, it can be used as a potent and natural component in crafting weapons, particularly bladed weapons like swords and daggers. The mushroom's essence, when infused into the metal, can make the weapon exceptionally sharp and deadly.
The Razorcap Mushroom might be discovered deep within a subterranean cavern or in a forest with mystical properties.