Flasks of oil normally hold half a liter of oil. To hit, roll a d20. A 20 means double damage, 2-19 means normal damage, a 1 means that the thrower catches himself on fire for normal damage. The oil normally does 1d6 dmg per half-liter and does 1d4 dmg per half-liter every successive round if the victim doesn't actively try to put out the fire.
I was entertaining the idea that this might have been too beneficial to the players, seeing as they've always been the ones lobbing the flaming oil flasks, but they recently seem to have abandoned the practice, so they must not seem to think it's so beneficial… I don't know.
Anyway, how do you run flaming oil flasks in your games? Is it too easy to use flaming oil flasks in my game? What about when the PCs start encountering tuckerized kobolds that use the flaming oil flasks and hit them on 2-20? Do you have any good stories that involve flaming oil or other hot or burning liquids?