Acid Arrow - duration

[Quasqueton]

3rd-level mage. Acid arrow spell.

Acid Arrow
Conjuration (Creation) [Acid]
Level: Sor/Wiz 2
Components: V, S, M, F
Casting Time: 1 standard action
Range: Long (400 ft. + 40 ft./level)
Effect: One arrow of acid
Duration: 1 round + 1 round per three levels
Saving Throw: None
Spell Resistance: No
A magical arrow of acid springs from your hand and speeds to its target. You must succeed on a ranged touch attack to hit your target. The arrow deals 2d4 points of acid damage with no splash damage. For every three caster levels (to a maximum of 18th), the acid, unless somehow neutralized, lasts for another round, dealing another 2d4 points of damage in that round.
Material Component: Powdered rhubarb leaf and an adder’s stomach.
Focus: A dart.

How many times do you roll the 2d4 damage? I thought it would be:
Once for the initial attack/hit.
Again at the beginning of the mage's second turn for the first round.
Then again at the beginning of the mage's third turn for the +1/3 levels round.
Total of 3 times.

But it has been argued that the "1 round" on the duration line refers to the initial cast/attack of the spell. So the total would be just 2 times.

To me, the spell "stats" don't match with the spell description.

What is right?

For comparison:

Acid Splash
Conjuration (Creation) [Acid]
Level: Sor/Wiz 0
Components: V, S
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Effect: One missile of acid
Duration: Instantaneous
Saving Throw: None
Spell Resistance: No
You fire a small orb of acid at the target. You must succeed on a ranged touch attack to hit your target. The orb deals 1d3 points of acid damage.

Note the duration is instantaneous, not 1 round.

Quasqueton

 

[AuraSeer]

For a third level mage, where the duration is 2 rounds, you roll damage twice for a total of 4d4 damage.

 

[dcollins]

I agree that the intent is to deal damage one time for each round indicated in the duration.

However, I could see how someone could argue that by convention a spell duration is supposed to end just before the caster's next turn, and therefore you'd get effectively one less round of damage (compare to summon monster which blinks out without an attack at the moment the duration ends).

 

[Diirk]

And that would matter why ? A summoned monster acts as soon as it appears, so a rat summoned for 2 rounds duration can attack as soon as its summoned, and again the following round, then disappears just before the casters turn on the 3rd round... so it got 2 attacks and lasted for 2 rounds. Seems to match up pretty well.

In the same way for a 3rd wizard casting acid arrow, you roll for damage once when you cast it.. this represents the damage for that round and is actually continual damage spread across the whole 6 seconds. Then you roll for damage at the start of the wizards turn on the 2nd round, and again its continual damage. Just before the start of the wizards turn on the 3rd round the spells duration expires.
So in total its lasted for 2 rounds (1 round + 1 per 3 levels, exactly as the 'Duration:' line states), and its applied damage 2 times.

In response to the original poster: If it worked how you described you thought it worked then it would be lasting 3 rounds when its only meant to last 2... each time you roll dice, it isn't an instant wound, its instead how much damage the acid does over the course of the entire round.. it takes 6 seconds for that damage to happen.

 

[Quasqueton]

OK, I see. I was thinking it was 2d4 for the initial hit, then 2d4 continual damage each round thereafter.

So, really, there is no initial "hit" damage. Seems kind of weird for a spell with the name "arrow" in it, and with an attack roll.

Quasqueton

 

[Plane Sailing]

I tried to post earlier today without success - basically just to say that IMO the key element is the continuous nature of acid arrow damage (which will force concentration checks), thus the damage is 2d4 during the first round in which the hit occurred, 2d4 in the second round and then it ends.

instantaneous effects have to cause damage at the instant they occur but don't do any continuing damage.

Cheers

 

[Christian]

Bingo. An acid orb with a duration of one round instead of being instantaneous would still only do 1d3 damage, but until the caster's next (scheduled) action, the target would have to make a Concentration check to cast a spell ...

 

[dcollins]

And that would matter why?

Summon monster with duration "1 round" --> gets 1 roll for damage.
Acid arrow with duration "1 round" --> gets 2 rolls for damage.

 

[Diirk]

Summon monster with duration "1 round" --> gets 1 roll for damage.
Acid arrow with duration "1 round" --> gets 2 rolls for damage.

No, acid arrow with duration "1 round" gets 1 roll for damage.... when you cast the spell. This damage then applies across the round as continual damage, and the spell fades at the start of the casters next turn with no additional rolls for damage.

However acid arrow never has a duration of 1 round because the minimum caster level is 3, which gives it a 2nd round to its duration but thats beside the point

 

[Diirk]

Duration: 1 round + 1 round per three levels

The arrow deals 2d4 points of acid damage with no splash damage. For every three caster levels (to a maximum of 18th), the acid, unless somehow neutralized, lasts for another round, dealing another 2d4 points of damage in that round.

Ok say you're a 2nd level caster casting acid arrow (I just remembered there's that weird feat in complete arcane or soemthing that lets you do that). The duration line says your acid arrow will only last 1 round, as you aren't high enough to qualify for any additional rounds yet. Then reading the description of how the spell works, it says we do 2d4 acid damage. Following that, there's some stuff about what happens if we have more caster levels, but we don't so we ignore that.

So in summary, our 1 round duration spell did damage once.

Can you explain how you can interpret it to do damage twice in one round dcollins ? I'm frankly mystified.