Grindstones are functional items featured in Lies of P. Grindstones temporarily imbue the player's weapon with special effects, similar to abrasives. After obtaining the Grinder Modification Tool from Venigni, players can equip Grindstones on the Grinder either by visiting a Stargazer or speaking with Venigni. The majority of Grindstones become available for purchase from Pulcinella by upgrading his inventory with Venigni Collections. Grindstones may only be used once per life but will be replenished by visiting a Stargazer. The number of uses can be increased through upgrades at the P-Organ.
Grindstones[]
| Name | Effect |
 Flame Grindstone |
Temporarily imbues weapon with Fire |
 Electric Blitz Grindstone |
Temporarily imbues weapon with Electric Blitz |
 Acid Grindstone |
Temporarily imbues weapon with Acid |
 Indomitable Grindstone |
Temporarily enhances Guard performance |
 Destruction Grindstone |
Temporarily increases weapon Stagger ATK |
 Satisfaction Grindstone |
Temporarily increases weapon Critical rate |
 Durability Grindstone |
Temporarily avoids Durability consumption |
 Perfection Grindstone |
Temporarily activates Perfect Guard when guarding |