Tree bark Sap

Potion, uncommon

This thick amber liquid is distilled from the sap of ancient oaks. When applied to a willing creature’s skin, it becomes as tough as stout wood for 1 hour, with the appearance of rough tree bark. The creature’s AC can’t be less than 16, regardless of what kind of armor it is wearing. However, the creature also becomes more flammable, having disadvantage on saving throws against fire.