Group Spell Casting

[Shoelessme]

Before I go looking to homebrew/flavor text this is there any rules for Spell casters working together to cast large nasty spells?
This is for NPC's not my player characters. I have a wizards academy/tower that will have to repel an army. I picture a conical building with a series of concentric circles that decrease in size as they go up. Using the runic circles from races of stone and some variant of aid another the low level casters on the lowest floor channel up etc, etc, till the archmage on the top floor alone finishes his spell and does anything from a rain of fireballs acrossed a square mile or perhaps a extreme storm that mass lightning bolts down. You get the picture. Mind this is not an epic campaign. This is just a cool side story that the player characters will see happening from a distance. We are also talking about alot of wizards working together. Most low level but the archmage will be pretty high.

Still if i use it for NPC's I should at least figure out what would happen if the player characters eventually tried, on a smaller scale, to copy it. I try not to let NPC's do anything player characters can not.

[eggynack]

Offhand, I'd say that red wizard from page 193 of the DMG might be what you're looking for. It grants the ability to use circle magic, which lets a group of people subsume their casting ability into a super spell. Another thing I thought of was cooperative spell from page 76 of complete arcane, which lets two or more casters cast the same spell at the same time for greater effects. The red wizard circle magic thing is probably closer to what you're looking for though.

[Jeff the Green]

Circle magic is probably more what you're after, but another option is incantations (http://www.d20srd.org/srd/variant/magic/incantations.htm).

[sleepyphoenixx]

The effects you describe are pretty firmly in the realm of epic magic. The caster can be assisted by any number of low level casters to lower the spellcraft DC.
So, unless you homebrew something you need the Archmage to be level 21 and develop an appropiate Epic Spell. Both the rain of fire and thunderstorm are described as possible applications of the Energy Seed.

[Shoelessme]

Circle magic is probably more what you're after, but another option is incantations (http://www.d20srd.org/srd/variant/magic/incantations.htm).

Those Incantations are kinda awesome. I have never seen nor heard of them before though... Do you know what book they are from? Complete Arcane?

So if I wanted the incantation to allow the archmage to cast any spell he has with a drastically increased area of effect and drastically increased range.
Ok, give me some time to calculate this. By the way what spell would have one of the largest unmodified area of effects? Something damaging not battlefield control. IE fire wall or some acid cloud.

[Jeff the Green]

Those Incantations are kinda awesome. I have never seen nor heard of them before though... Do you know what book they are from? Complete Arcane?

Like all the variant rules in the SRD, it's in Unearthed Arcana.


So if I wanted the incantation to allow the archmage to cast any spell he has with a drastically increased area of effect and drastically increased range.
Ok, give me some time to calculate this. By the way what spell would have one of the largest unmodified area of effects? Something damaging not battlefield control. IE fire wall or some acid cloud.

Lessee. I'd say it's probably a Transmutation effect. You could probably do one each of level 5, 7, and 9, each increasing area of effect and range by some factor. The Knowledge (arcana) DC would probably be 18 before material, backlash, or XP components (32 [base] - 4 [medium to self] - 10 [101+ casters]), which an archmage could make trivially even if he couldn't take 10 (even at level 10 he should have a modifier of at least 17).

[Shoelessme]

Like all the variant rules in the SRD, it's in Unearthed Arcana.



Lessee. I'd say it's probably a Transmutation effect. You could probably do one each of level 5, 7, and 9, each increasing area of effect and range by some factor. The Knowledge (arcana) DC would probably be 18 before material, backlash, or XP components (32 [base] - 4 [medium to self] - 10 [101+ casters]), which an archmage could make trivially even if he couldn't take 10 (even at level 10 he should have a modifier of at least 17).

Awsome. I was thinking use a spell with already a huge area, say firestorm (i know its not a wizard spell but its what i could think of real quickly) with 2 10ft cubes per level. Archwizard is lvl 15 so thats 3000 square feet already. The rules give you a +3 dc to double the area and +2 to the dc to increase the range by 1 step. Not sure if you can double it multiple times. It doesn't say you can't i guess. Add in another -4 for having a permanent expensively gemed focus circle in the wizard tower, maybee some xp costs and some incense to burn.

If i did the math right i could have a firestorm that could hit 24,000 square feet (or 960 5x5 squares and 10 ft off the ground to the ground) that had a range 3 steps up from long (not sure what this becomes honestly) that would take 4 hours to incant with 5 dc 24 skill checks (arcane, spellcraft, and geography for targeting) and all participants are exhausted after the spell ends.

[Jeff the Green]

Awsome. I was thinking use a spell with already a huge area, say firestorm (i know its not a wizard spell but its what i could think of real quickly) with 2 10ft cubes per level. Archwizard is lvl 15 so thats 3000 square feet already. The rules give you a +3 dc to double the area and +2 to the dc to increase the range by 1 step.

Actually, those modifiers are for the range and area of the incantation itself. See this?:

Transmutation
DC 32; Range: Medium; Target: One creature or 20 cu. ft. of matter; Duration: Rounds; Saving Throw: Fortitude half (often harmless); Spell Resistance: Yes.

If you wanted to make it long range you'd add 2 to the DC, and if you wanted to make it affect up to 40 cu. ft. of matter you'd add 3. I'd make the level 5 version quadruple range and area, the level 7 one multiply them by eight, and the level 9 multiply them by sixteen.

[Shoelessme]

Actually, those modifiers are for the range and area of the incantation itself. See this?:


If you wanted to make it long range you'd add 2 to the DC, and if you wanted to make it affect up to 40 cu. ft. of matter you'd add 3. I'd make the level 5 version quadruple range and area, the level 7 one multiply them by eight, and the level 9 multiply them by sixteen.

Perhaps, but maybee im misunderstanding something. By that definition then the target of the ritual would be the archmage. Not the army. You target him and transmute one of his spells?

[Jeff the Green]

Perhaps, but maybee im misunderstanding something. By that definition then the target of the ritual would be the archmage. Not the army. You target him and transmute one of his spells?

Yep. The text of the incantation would be something like this:


You use the magical power siphoned from your apprentices to boost the power of your own spells. The next spell you cast has its range and area multiplied by four.

[Gildedragon]

Alternatively, to get the big area effects you might want to look into war-spells from dragon magazine. Essentially +1 to spell level, +feat, +costly focus for an increased area.

[Flickerdart]

Psionics does it better - Metacaoncert (http://www.d20srd.org/srd/psionic/powers/metaconcert.htm) is exactly what you need.

[Emperor Tippy]

Psionics does it better - Metacaoncert (http://www.d20srd.org/srd/psionic/powers/metaconcert.htm) is exactly what you need.

Except it doesn't actually work as written.

1) Does the metaconcert get its own collection of actions, only take up the conductors actions, or take up every participants actions?

2) What is the ML of the metaconcert?

3) What is the AB of the metaconcert?

4) How is line of effect and line of sight determined? From each participant, from the conductor, from a metaconcert entity that is produced, or from something else entirely?

It's a great idea but as written the power is unusable.

[Flickerdart]

Except it doesn't actually work as written.

1) Does the metaconcert get its own collection of actions, only take up the conductors actions, or take up every participants actions?

2) What is the ML of the metaconcert?

3) What is the AB of the metaconcert?

4) How is line of effect and line of sight determined? From each participant, from the conductor, from a metaconcert entity that is produced, or from something else entirely?

It's a great idea but as written the power is unusable.
Seems pretty clear to me - "directs the efforts of the group" means the conductor is the one that takes actions for the metaconcert, determines its ML, AB, and line of sight and effect from it to stuff. I mean, you could choose not to read it that way, in which case it doesn't work.