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AsteriX97
2022-10-19, 12:53 PM
Hi, guys!

In my previous thread, I asked about how does the Empower Spell feat work, because I was creating a custom spell in Neverwinter Nights that deals damage to a single target.

Now, however, I'm in a similar situation, except this time, I'm creating an AOE damage spell, but I need to confirm how the damage rolls for AOE spells work because I've never read any rulings about this before.

Let's take Fireball for example. If you cast a Fireball spell, with a CL of 10, do you:


Roll a 10d6 once, and apply that damage (or half of it on a successful save), to all the targets within the area-of-effect of the spell, or
Do you roll 10d6 for each enemy caught within the area-of-effect, and apply 10d6 points of damage to each enemy individually?

Are there any official rulings that state which of these two methods should be used, since I can't find anything on it, only mixed opinions.

Some say the damage should be rolled only once and be the same for all enemies, while others say the damage should be rolled separately for each enemy, so I'm a little bit confused about which method I should use.

Meanwhile, the official description for a Fireball spell looks like this:


Fireball
Evocation [Fire]

Level: Sor/Wiz 3
Components: V, S, M
Casting Time: 1 standard action
Range: Long (400 ft. + 40 ft./level)
Area: 20-ft.-radius spread
Duration: Instantaneous
Saving Throw: Reflex half
Spell Resistance: Yes

A fireball spell is an explosion of flame that detonates with a low roar and deals 1d6 points of fire damage per caster level (maximum 10d6) to every creature within the area. Unattended objects also take this damage. The explosion creates almost no pressure.

You point your finger and determine the range (distance and height) at which the fireball is to burst. A glowing, pea-sized bead streaks from the pointing digit and, unless it impacts upon a material body or solid barrier prior to attaining the prescribed range, blossoms into the fireball at that point. (An early impact results in an early detonation.) If you attempt to send the bead through a narrow passage, such as through an arrow slit, you must “hit” the opening with a ranged touch attack, or else the bead strikes the barrier and detonates prematurely.

The fireball sets fire to combustibles and damages objects in the area. It can melt metals with low melting points, such as lead, gold, copper, silver, and bronze. If the damage caused to an interposing barrier shatters or breaks through it, the fireball may continue beyond the barrier if the area permits; otherwise it stops at the barrier just as any other spell effect does.

Material Component: A tiny ball of bat guano and sulfur.
~ PHB p.231

I put emphasis in the first sentence about the damage roll, but even then, it doesn't explicitly say that you should roll only once, or roll for each target.

Any suggestions on which of these two methods is the proper method to be used?

Telonius
2022-10-19, 01:14 PM
It's explicitly written out in a bit of text that didn't make it into the SRD: Players Handbook p. 169-170, describing Burning Hands. You roll once and apply the damage to everything that's in the area (saving for half if applicable).

Totally agree that this should be much more explicitly stated, and absolutely should have been in the SRD. (Most likely wasn't because the paragraph was full of the iconic character names).

Biggus
2022-10-20, 12:41 AM
It's explicitly written out in a bit of text that didn't make it into the SRD: Players Handbook p. 169-170, describing Burning Hands. You roll once and apply the damage to everything that's in the area (saving for half if applicable).

Totally agree that this should be much more explicitly stated, and absolutely should have been in the SRD. (Most likely wasn't because the paragraph was full of the iconic character names).

Thank you, it'd never even occurred to me that rolling damage separately might be an option (imagine what it would be like at high levels: roll 20d6 for each of the 12 enemies caught in your spell's area...) but it's good to know I've been doing it right.

AsteriX97
2022-10-20, 05:24 AM
It's explicitly written out in a bit of text that didn't make it into the SRD: Players Handbook p. 169-170, describing Burning Hands. You roll once and apply the damage to everything that's in the area (saving for half if applicable).

Totally agree that this should be much more explicitly stated, and absolutely should have been in the SRD. (Most likely wasn't because the paragraph was full of the iconic character names).

Ah, I see, nice catch! Thank you for pointing that out!

Here's the quoted text from the PHB for anyone interested in it:


Burning Hands: Mialee wants to cast burning hands on some Small centipedes, and she wants to hit as many of them as she can. She moves to a spot that puts three centipedes within 15 feet of her, but none next to her, so they can't attack her while she is casting.

She chooses a direction and casts her spell. A cone of magical flame shoots out 15 feet, catching the three centipedes in its area. Mialee's player rolls 1d4 to see how much damage each centipede takes and gets a result of 3. The DM makes a Reflex save (DC 13 for one of Mialee's 1st-level spells) for each centipede, and only one succeeds. Two centipedes take 3 points of damage each and drop. The lucky one takes half damage (1 point) and survives.
~ PHB p.169-170

Darg
2022-10-20, 07:13 AM
Now we just need some obscure text to to tell use whether Whirlwind Attack uses one attack roll or one for each enemy. I prefer the one roll for simple resolution.