Damage over time and damage triggered effects.

[Fero]

I am curious if the community has ever reached consensus as to how damage over time spells (e.g. Wall of Fire) and abilities that trigger when a spell does damage (Fell Enervate, Stormcaster Thunderbolt ability, etc.) Does the ability trigger each time the spell does damage or only the first time?

I am also curious how such abilities work with damage on trigger spells (such as fire shield), weapon like spells, and multi use touch spells (e.g. chill touch).

Thank you for your insights!

[Biffoniacus_Furiou]

I believe the official answer is that a given creature only receives a carrier effect (Fell Drain, Fell Frighten, etc.) the first time it takes damage from a given spell.

If you cast a Fell Frighten Fire Shield, a creature becomes shaken the first time it hits you and takes damage from the shield, but not from subsequent instances of damage from that fire shield. You could cast a red and a blue fire shield this way, and each creature that attacks you would become frightened from the escalated condition of both shaken effects, but only the first time it attacks you.

Three Thunders typically has a different ruling, since it specifies, "...the spell concludes with a mighty thunderclap that stuns all creatures that take damage from the spell for 1 round unless..." So instantaneous spells have it occur immediately, but spells that last a round or more will have it occur at the end of the duration. However, I don't recall anything official on this so it's up to your DM to decide. Many may give it the same ruling as above and say it occurs the first time a given creature is damaged by the spell, considering it deals sonic damage.

Also, Twin Spell is still a single spell that has its effect occur twice, and this should also apply to carrier effects such as above, allowing those to hit a given creature twice, as long as they're damaged by each instance of the twinned spell.

[Gruftzwerg]

Beginning at 5th level, you use your knowledge of the storm to add the power of thunder to your lightning-based spells. Any spell you cast that deals electricity damage also deals an extra 1 point of sonic damage per spell level and stuns any creature damaged by the spell for 1 round (Fortitude save negates; DC equals the save DC of the spell, even if the spell wouldn't normally allow a save).

any spell you cast that deals electricity damage != any time your spells deals electricity damage

You get the benefit for each cast and not for each time you deal damage. It's imho simple and obvious if you know for what key terms you should look out for.

Dunno if the other examples follow the same wording as this one. But this should give you an idea for what key-terms you need to look out for. If you should find anything that is still problematic, give us a rule quote and we'll see if we can solve the riddle.

[Melcar]

Also, Twin Spell is still a single spell that has its effect occur twice, and this should also apply to carrier effects such as above, allowing those to hit a given creature twice, as long as they're damaged by each instance of the twinned spell.

You really want a twnned, repeating, plitray! For a total of 8 applications!

[Biffoniacus_Furiou]

You really want a twnned, repeating, plitray! For a total of 8 applications!

Nah, best use is having your Incantatrix apply metamagic to a spell after it's cast. Use Detect Magic with Permanency, so you only need to concentrate to activate it, and use the Swift Concentration skill trick so it's a swift action 1/encounter. Cast that with Snowcasting so it has the cold subtype, so you can add Flash Frost Spell and Heighten it at least one level so it deals damage. Add Twin Spell so it goes off twice, Fell Frighten and Fell Drain so they get hit with each twice. Widen Spell for good measure so it's a 120-ft. cone. You can include Energy Substitution: Electricity and Born of the Three Thunders if your DM rules that the stun goes off when it deals damage, or when the effect ends (i.e. you stop concentrating), which also adds some variety to the damage to help avoid an energy resistance allowing a target to ignore it.

So, as a swift action you create a 120 ft. cone that detects magic twice, covers the area in frost which may cause slipping, deals 1 electric damage, 1 electric damage, 1 sonic damage, and 1 sonic damage (for purposes of energy resistance), causes anyone damaged to become shaken twice escalating to frightened, anyone damaged to gain two negative levels, and anyone damaged needs to save vs being knocked prone and stunned. All the carrier effects will only work once against a given opponent, so hit your allies with it once outside of combat and never worry about catching them in the area during a fight.

[Biggus]

Widen Spell for good measure so it's a 120-ft. cone.

Minor detail: Widen Spell doesn't work on cones, only a burst, emanation, line, or spread.

[Troacctid]

Nah, best use is having your Incantatrix apply metamagic to a spell after it's cast. Use Detect Magic with Permanency, so you only need to concentrate to activate it, and use the Swift Concentration skill trick so it's a swift action 1/encounter. Cast that with Snowcasting so it has the cold subtype, so you can add Flash Frost Spell and Heighten it at least one level so it deals damage. Add Twin Spell so it goes off twice, Fell Frighten and Fell Drain so they get hit with each twice. Widen Spell for good measure so it's a 120-ft. cone. You can include Energy Substitution: Electricity and Born of the Three Thunders if your DM rules that the stun goes off when it deals damage, or when the effect ends (i.e. you stop concentrating), which also adds some variety to the damage to help avoid an energy resistance allowing a target to ignore it.

So, as a swift action you create a 120 ft. cone that detects magic twice, covers the area in frost which may cause slipping, deals 1 electric damage, 1 electric damage, 1 sonic damage, and 1 sonic damage (for purposes of energy resistance), causes anyone damaged to become shaken twice escalating to frightened, anyone damaged to gain two negative levels, and anyone damaged needs to save vs being knocked prone and stunned. All the carrier effects will only work once against a given opponent, so hit your allies with it once outside of combat and never worry about catching them in the area during a fight.

1. You can't add extra damage unless you are dealing damage already. Flash Frost doesn't work.
2. You can't use the same action to concentrate on two spells at once. Twin Spell doesn't work.
3. You can't extend a spell's area beyond its range. Widen Spell doesn't work.
4. The spell doesn't conclude at all because it's permanent—its duration doesn't end when you stop concentrating. Born of the Three Thunders doesn't work.
5. Fear effects from the same source don't stack. Fell Frighten stacking doesn't work.
6. As a corollary to 1, none of the effects that trigger on damage work.
7. The slippery effect triggers when the spell is cast and only lasts 1 round. Flash Frost really doesn't work.

Did I miss anything?

[Elenian]

1. You can't add extra damage unless you are dealing damage already. Flash Frost doesn't work.

I don't think that follows from the natural language use of 'extra' - it could just mean 'in addition to the spell's usual effects', right?

[Troacctid]

I don't think that follows from the natural language use of 'extra' - it could just mean 'in addition to the spell's usual effects', right?

That's not really what this thread is about, so I don't want to dive too deep into it. I'll just ask you this: can a rogue deal sneak attack damage on the unarmed touch attack to initiate a grapple?

[Zanos]

That's not really what this thread is about, so I don't want to dive too deep into it. I'll just ask you this: can a rogue deal sneak attack damage on the unarmed touch attack to initiate a grapple?

Probably, considering you can deal "extra" sneak attack damage with weaponlike spells that deal no damage at all.

That said, permanency replaces the duration of the spell. It would no longer be concentration, it would be permanent. You can't toggle it.

[Crake]

Probably, considering you can deal "extra" sneak attack damage with weaponlike spells that deal no damage at all.

Citation needed? Ability damage is still damage, in case that was going to be your go-to.

[Zanos]

Citation needed? Ability damage is still damage, in case that was going to be your go-to.

That rule also applies to spells that inflict negative levels, which are not damage.

[Darg]

You really want a twnned, repeating, plitray! For a total of 8 applications!

Make it echoing to do it all again!