Cooperative Spell - one effect or more than one?

[Kershek]

In the Cooperative Spell feat from Tome & Blood, when two spellcasters cast fireball cooperatively, is there one instance of the fireball or two? Can someone reference proof of the answer?

Here's the spell:

Cooperative Spell
You can cast spells to greater effect in conjunction with
the same spell cast by another.
Prerequisites: Any other metamagic feat.
Benefit: You and another spellcaster with the Cooperative
Spell feat can simultaneously cast the same spell (at the
same time in the round). You must be adjacent to one another
when casting cooperatively. Add +2 to the save DC against
cooperatively cast spells and +1 to caster level checks to beat
the target’s spell resistance (if any). Use the base DC and
level check of the better caster. A cooperative spell uses up
a spell slot of the same level as the spell’s actual level.
Special: For each additional caster with this feat casting
the same cooperative spell simultaneously, the spell’s
save DC and caster level check both increase by +1. When
more than two spellcasters cooperatively cast a spell, each
must be adjacent to at least two other casters.
For example, four spellcasters (two wizards and two sorcerers)
standing in a circle all possess Cooperative Spell.
Three of them ready an action to cast fireball when the
member with the lowest initiative takes her action, also casting
fireball. The base DC of the Reflex save is equal to the
highest individual save DC among the cooperative casters,
as determined by their relevant ability scores or other feats
(such as Spell Focus), special abilities, or items. In this case,
one wizard has Intelligence 18, which ties with a sorcerer’s
caster level check, which gains a +4 modifier.

 

[Maitre Du Donjon]

By the reading of the feat, IMO, everyone cooperating actually casts a spell. In their example, 4 fireballs actually go off simultaneously.

Maitre D

 

[Majoru Oakheart]

"The base DC of the Reflex save is equal to the
highest individual save DC among the cooperative casters,"

It makes it sound like there is one DC, not many. Plus, I always assumed that the point of the feat was wizards all combining their efforts to make one powerful spell.

 

[Cheiromancer]

All the DC's are the same, but IMHO there is a separate spell effect for each caster.

If there was only one spell effect, the feat would have to specify who makes decisions regarding the spell (i.e. targets).

It doesn't, and neither does it say that the casters together only produce one spell effect. So other than what is specifically changed (DCs and such), each caster should produce their own spell effect.

There are ways a DM can abuse this interpretation, but I don't know any way a player could.

 

[Stalker0]

Hmm, tricky to say. Based on wording I'm unsure. Based on usefulness of the feat, I would highly recommend allowing each one a spell. Using upon the slots and time of two caster to produce one spell that's a little bit better is really crap imo. I would let each one have there own spell.

 

[Li Shenron]

Given the general design attitude of WotC, I am afraid it is supposed to be just one spell, with increased DC and caster level.

Yes, it's not a wonderful improvement, but still it has +0 level equivalent and I really think that a Wizard with this feat can just prepare all spells cooperatively, in the case she later casts them so, but is not compelled to do so (in the sense that a cooperative spell could be cast alone also, at least it doesn't require to choose at preparation how many casters will cast it).

It would not be overpowering to allow 2 Wiz to get both this feat and cast cooperative Fireballs with twice the effect, but I don't think it matches with the typical design prudence of WotC.

 

[ThoughtfulOwl]

I always intended it to pull off only a single spell; otherwise you could have a high level caster with DCs already pumped through the roof "lend" it to his gang of lower level goons and even have it additionally improved at no cost other than the fact that all must cast the same spell.

If you think that a single spell makes it too weak, consider that fireball is a poor example (better if each casts it on his own); where Cooperative Spell is useful is with all-or-nothing effects against enemies with high saves or high spell resistance.

Think about the Tarrasque, or many dragons; a bunch of not-so-high-level casters, who ordinarily would be squished, could petrify one of those critters with Flesh to Stone and worry only about a natural 20 on the saving throw.

 

[Cheiromancer]

I always intended it to pull off only a single spell; otherwise you could have a high level caster with DCs already pumped through the roof "lend" it to his gang of lower level goons and even have it additionally improved at no cost other than the fact that all must cast the same spell.

The situation you describe can only be arranged by the DM. A player normally has just one character, maybe a cohort or two, and two or three people just aren't enough to abuse the feat. If there is a high level caster with a gang of spellcasting underlings, it is going to be an NPC controlled by the DM.

 

[Li Shenron]

When I first read T&B I thought this feat was indeed designed for NPCs, since your party is rarely going to spend 2 feats on this, if there are 2 similar spellcasters at all. I thought this feat was intended for rituals or similar casting, to do outside combat.

The feat says you get a bonus to caster checks for the purpose of beating SR only, which is a pity, because if it has increased caster level also for setting a higher DC against dispelling, it can help the DM design an adventure where it is very difficult to get rid of a permanent spell with a simple Dispel Magic (possibly disposing the quest of the whole adventure), if the spell was cast by a cabal of 20 cooperative spellcasters.

Anyway, if you have 2 casters with CS you can make them use this feat when crafting a spell-trigger or spell-activation item with increased DC and CL for SR without any additional cost to the item (except maybe the double material components) since the spell level remains unchanged.