Oil (flask)
Type
Cost
1 sp
Weight
1 lb
Oil usually comes in a clay flask that holds 1 pint. As an action, you can splash the oil in this flask up to 20 feet, shattering it on impact. Make a ranged weapon attack against a target creature or object, treating the oil as an improvised weapon. On a hit, the target is covered in oil. If the target takes any fire damage before the oil dries (after 1 minute) it takes an additional 5 fire damage from the burning oil. You can also pour a flask of oil on the ground to cover a 5-foot-square level area. When lit, the oil burns for 2 rounds and deals 5 fire damage to any creature that enters the area or ends its turn in the area. A creature can take this damage only once per turn.
Source