I'll come out and clearly say why: As I near the very end of my work on the Book of War mass-combat system for D&D, I finally got to test the high-end magic for wizards, near the end of the book. Assume that all such wizards are level 10+ (e.g., the Swords & Spells example in the last post). Then further assume that every such wizard has either a wand of fireballs or a wand of lightning bolts. This seems reasonable because: (a) if you're a wizard on the battlefield, it seems like you'd want to have such a device (e.g., they're common even in Holmes Basic D&D for levels 1-3), (b) it simplifies the number of spells we'll likely see in use, (c) it simulates the Chainmail expectation that these abilities are effectively at-will throughout a standard battle, and (d) the assumption is explicitly baked into certain editions of D&D (e.g., see 3E stock NPC rosters for wizards).
So fireballs are common, important, and very powerful. At inception, they had a limiting factor of a special targeting rule (declare target and range of shot, as befit their special "missile" class and catapult origin), but that's highly dependent on player skill (much more so than estimating a basic cavalry-charge or missile-fire range), something that really only works in the context of miniatures on an open, un-gridded playing surface. And even then, perhaps only if our targets are masses of possibly hundreds of figures per unit. And so perhaps that's why they were given such large areas-of-effect, to possibly compensate for this targeting challenge. (?)
The targeting language was explicitly copied forward throughout every edition of D&D, but the assumptions no longer really worked. Play without miniatures? Then the mechanic is nonsensical. Play on a grid? Then the mechanic is trivial. Play D&D with just a few miniatures per side? Then targeting is extremely difficult (even with minis on an open table). Use the space-expanding rule as a counter-balancing measure? Then it's extremely complicated and almost too dangerous to use the spell underground.
My guess is that almost nobody actually enforced that targeting rule in the AD&D era and beyond. It's so unlike how any other spells are targeted that you'd easily forget about it. And the rulebook language got "submerged" by rewriting it in the in-game character's perspective ("The magic-user points his or her finger and speaks the range (distance and height) at which the fireball is to burst." [AD&D PHB]), so it's no longer clear if the player actually needs to do the same.
What I found in my game is that if the wizard can just drop fireballs anywhere they want with pinpoint accuracy, then they can continually target enemy heroes with every shot and quickly eliminate them from the game (notice how that never happened in Gygax's example of play in Swords & Spells, even though other spells like hold person targeted enemy heroes without difficulty). On the other hand, if we enforce then age-old "declare range" rule, then it's almost overwhelmingly difficult to hit anything (as usual, for mobile targets in the open field) unless you've got hundreds of figures per unit, or are somehow cheating by pre-measuring. (And I confess that the last time I played, in desperation, I resorted to comparing to known grain marks on the table surface -- although I still lost.) And in that case, the canonical fireball becomes basically useless.
So, what's the best thing to expect from the game now? How are most people using fireballs; are they balanced and a reasonable thing to use; and how do they fit in with the traditions of classic D&D? I ask this both for Book of War and also a potential Book of Spells update. Here's a brainstorm of every mechanic I could think of over the past few weeks:
- Pinpoint any target in range as desired (as other spells).
- Declare target & range of shot (legacy catapult-like rule)
- Declare target & apply some variation (like a grenade or cannons).
- Declare target & check "to-hit" or similar, else apply variation.
- Target a mass unit freely, but roll for specific figure hit (disallowing solo heroes as targets).
- Target at will, but set a damage cap for massed figures (as in Swords & Spells)
- Declare target & range & also cap damage for massed figures.
- Something else entirely.
See poll results here.