I think my way of doing it is cooler by a country mile, but they seem to be on the money with their arguments that the dreaded Rules As Written support lamer, non-volumetric fireballs. I think Delta is wrong about my fireball rules being too complicated, but he plays OD&D so I expect him to want things even simpler than I do. My fireball rule is not complex, but it does stop play in its tracks while the DM figures out where all that magical fire goes. I find that the pause builds suspense. Even in combat not every moment needs to be go-go-go, as long as the pauses are for effect and not to look up the AC of lizard men.
(Seriously, on that last point, a lot of time can be saved by knowing a handful of monster stats and thinking comparatively. What monster do you know something about is it close to in hit dice? Is it as tough as an orc? A gnoll? A hill giant? Is its hide tough as leather, hard as plate, or roughly in-between? Should one blow from it have a chance of outright killing a man, or be likely to do so? Answering these questions can be much quicker than looking up the stats. Also: you would be astounded by the number of big, scary monsters my players have fought that were mechanically the exact same as an ogre.)
Anyway, I got to thinking that the same rules I threw out yesterday for fireball volumes could be used for red dragon breath. Using the BX D&D rules, a red dragon breaths out a cone 90' long that's 30' wide at the far end. That comes out to 21 cubes of 10' x 10' x 10'. That could make life interesting in small spaces.
|red/white cones, blue/black lines, green clouds|
Green dragon breath takes up even more space! Their cloud of deadly gas comes out to 40 cubes in BX. The AD&D1 dimensions are slightly larger, resulting in 60 cubes of volume. Of course, poison gas doesn't behave the same way as a blast of fire. I wouldn't roll to blow open doors and I would assume the gas is heavier than air, so it would only float down or sideways, only going up if there was no other place for it.
White dragon cones are slightly smaller than red dragon blasts, amounting to 19 cubes in BX but only 11 1/2 in AD&D1. Whether the cold blasts of a white dragon behave like fire blasts is up to the individual DM, but I like the idea. Blue dragon breath ought to follow the same rules as lightning bolt spells, which is maybe another post for another time. The 60' long, 5' wide stream of black dragon acid does amount to much, only 1.1 cubes. However, that equals about 8,800 gallons of acid! Where that drains after each blast might be worth considering.