Oil of Fiery Burning
Every now and then an alchemist forgets the warning label for these volatile oils; with explosive results.
When this oil is exposed to air it instantly combusts, inflicting damage to d3 nearby creatures. The usual use of the oil is as a thrown weapon, like a grenade or Molotov cocktail. If used in this way, the attack is a basic ranged attack. The damage itself differs by tier. If the stopper is removed, a DC: 20 dexterity check must made to stop the flask exploding in your hands!