There are plenty of examples in the sixth world of magical groups coming together to achieve an aim greater than a single magician could achieve.
Ritual sorcery, warding teams creating larger, longer lasting and more powerful wards, the astral manipulations of the Blood mage gelsalt, initiation groups and of course, the biggest of them all, being the Great Ghost Dance itself.
As such the concept for ritual conjuration would seem to be in good company, so why does it not exist?
In short because no balanced rules exist for it.
Unlike sorcery which has the same rules mechanics for both shamanic traditions and hermetics, conjuring has multiple differences between styles.
So the rules need to work for Wu jen to witchs and psionics to hougans.
I have tried to create rules that do not favour either the shamanic or the hermetic traditions but are useful to both while preserving their stylistic concept.
I have read through some of the threads on the boards concerning this and hope I have succeeded.
If you believe I haven't, well you don't have to use them now do you.
If you believe I have, I hope you these prove useful in the way of game reality ideas and run concepts.

Ritual Conjuring

Requirements
The ritual team must consist of magicians of the same magical tradition.
Shamans of different totems may work together in the same ritual team.
The maximum size of the ritual team is the conjuring skill of the Ritual Leader (see below).
During the ritual all members of the ritual team must be astral perceiving.

Shamans must perform the ritual in a local, which is in the correct domain for the intended nature spirit.
Mages must have an appropriate hermetic circle with a rating at least equal to the force of the elemental they intend to summon. Also they require access to a conjuring library that has a rating at least equal to the summoned spirits force as per normal rules.

The Ritual Leader
One magician is elected from the ritual team to lead the ritual. This is usually the most powerful initiate in the group.
The Ritual Leader receives control of all the summoned spirit’s services/ favours. The spirit is counted for control purposes in everyway as if the ritual leader had summoned the spirit individually and all normal rules apply accordingly.
The maximum force spirit that the ritual team may conjure is twice the magic attribute of the Ritual leader.
Only the Ritual Leader’s Totem modifiers or hermetic school modifiers apply towards the ritual.
If the Ritual Leader is an initiate with the metamagic discpline of Invoking the ritual team may attempt to summon a appropriate greater form spirit.
Finally because it is the Ritual Leader that is considered the controller of the summoned spirit, should they become unconscious or die from the drain of the ritual, the summoned spirit becomes uncontrolled.

Mechanics
Shamanic ritual teams take one minute per force of the summoned spirit in chanting, dancing and playing instruments to perform the ritual.
Hermetic ritual teams require and additional 500 nuyen of ritual materials per force of the summoned spirit on top of the usual 1000 nuyen per force. And additional half an hour per force of the summoned elemental is needed to perform the ritual on top of the standard time. (One hour per point of force of the summoned elemental.)

The ritual is considered an exclusive action so pools do not refresh.
Foci and Ally spirit dice may only be added once over the course of the conjuring ritual.
Only the Ritual Leader’s totem modifiers or hermetic schools modifiers apply towards the ritual Conjuring pool.

At the beginning of the ritual all ritual team members must astrally perceive, they then contribute up to their full conjuring dice into the ritual’s Conjuring Pool.
They may at this stage hold back dice to aid in their personal drain resistance test.
The Conjuring pool is now considered the conjuring skill of the ritual team.
The Conjuring pool dice are then assigned either to the Summoning pool (used to summon the spirit) or the Drain Resistance pool (which are held for drain phase of the ritual).

Summoning
Roll the Summoning pool against the TN equal to the force of the summoned spirit. The number of successes is the number of favours/services and the karma pool of the spirit.
For Invoking use the entire Summoning pool again for the Invoking test to determine if the spirit grows into its great form, as it is considered the summoning skill of the group.

Drain
Each magician now resists drain as if they had summoned the spirit individually as per the standard rules. However Drain Resistance pool dice may be assigned for their individual resistance tests, in the same manner as spell defence dice.

For Invoking rituals re-roll these assigned totals for the second drain resistance test.

Withdrawing from the ritual
Should a member of the ritual team withdraw from the ritual before its completion, the dice they contributed to the Conjuring pool subtracted from the Summoning pool before the spirit is summoned or the Drain Resistance pool after the spirit is summoned.
Should this empty the Summoning pool the ritual aborts and every on takes drain immediately.
If the case of leaving before the spirit is summon and the Summoning pool does not empty completely, the magician takes no drain.
Withdrawing after the spirit is summoned the magician takes drain normally without the benefit of the Drain Resistance pool.

Astral Concerns
The summoned spirit possess the astral signature of the Ritual Leader.
At the physical local for Shamans and the hermetic circle for mages, the astral signature is a composite of the entire ritual team, as they are considered a single astral enity. As such to identify the individual astraql signature of a participating magician requires an Assessing test with five successes plus half the number of the ritual team.

Thanks I had not considered an initiate's astral pool. The answer there I think should be no, this is because I am reading the use of the astral pool to be used in astral actions. Astral perception, astral combat etc
It is not mentioned in ritual sorcery so I'll go for the above.

On your second point: yes. It is the sum of relvent foci and/or ally spirit dice.

Finally by local I mean the physical place in which the ritual was performed. Shaman's don't need a shamanic lodge to perform ritual conjouring but need to be in a place which has the correct domain for the summoned spirit.

How would you deal with a spirit of the power that ritual summoning could create? We are talking the stat line of a dragon with immunity to normal weapons. What is the check on a group of mages doing this and how could someone protect themselves?

I checked the probabilities before I posted so it is unlikely that a group would be able to summon a spirit at force nine or ten without several of the ritual team dying of drain. For a ritual team of starting character conjurers with charisma 6 and conjuring 6, it raises the chance of successfull summoning/having one or two services on high force spirits (Force 6-8 ) Edit depending on the number of participating magicians.
Force 9 and above will result in deadly physical with a very high power drain, presuming they have body 4 or less thats instant kill if they don't stage down. Also from a realism point of view even for a force 8 spirit the ritual team as a whole would be in for a long hospital stay. Edit: (Moderate to Serious physical wound)

Sorry I did not actually answer your question, only outline the limits of high force ritual conjuring.
A high force spirit would be stopped with the usual methods of stopping spirits, a conjurer, a mob of friendly spirits, high force wards, weapon foci, mana bolt and the ever popular polearm and high charisma for the non awakened.

A group of terrorist initiate 6 mages with force 6 power foci that don't mind being knocked out as long as the lead stays conscious could summon a force 12+ great form Fire Elemental with the storm strike ability and level a city.

While some might think that an interesting run it scares me, but then anyone can crash an airplane into a football stadium, snipe people from the top of a school building, set off a pocket nuke, or level a planet with drop bears so I guess in that sense it just adds to the paranioa of shadowrun.

Erm the amount of money and karma/time that a grade 6 magician needs to initiate and to buy/create a rating six power focus is awesome. In the original term of the word.
Simply finding such a power focus would be staggeringly hard or equally difficult to create. The same applies to a rating six spirit focus.

To have six such magicians of the same tradition agree to come together to perform such a task is, well, pushing believability.
We are talking about magicians that are the best in the world, initiated into double digit magic attribute. They could happily summon a force eight spirit by themselves.
But if they did then yes we talking about the level of power that caused three volcano's to erupt at the same time.

It's up to the individual on how they run their game but the example is extreme don't you think?

Edit:
I just worked out the statistics on summoning a force 12 greater elemental. It just won my Darwin award.
12 dealy stun followed by 24 deadly stun. Everyone falls over. There simply isn't enough dice to invoke or survive the drain.

QUOTE (Pendaric)
presuming they have body 4 or less thats instant kill if they don't stage down.

Are you suggesting that conjuring drain be staged down with Body rather than Charisma?

No, I was pointing out the instant kill rules (deadly over damage) on the power of wounds from I think cannon comp. Edit main rules book curse my rulefu

Yes I meant the word locale not local. Dyslexic and rushed sorry.

As to astral pool use, it specifies that the astral pool can not be used in magical skills. So it may not be added to the Conjuring pool thus not to the Drain Resistance pool which is split up to add in the personal resistance tests at the end of the ritual.
I do agree with you though that perhapes it could/should be useable on the personal drain resistance test.
Much as if dice had been held back for personal use at the begining of the ritual and not contributed to the Conjuring pool.

I think the time taken needs working on. I see here the first real chance to explain the Great Ghost Dance, and would even like to see a possible example of how that worked out (how many shamans, what Initiate grades, etc) Maybe for Each additional Hour that a shamanic group spends dancing or whatever it is they need doing, the drain level is reduced by 1. (making that 12 deadly stun followed by 24 deadly stun, a negotiable stun level after 24 hours of uninterrupted fasting/dancing )

This looks like a neat idea, although the initial post needs some good editing before it's rulebook quality. I also notice you refer only to shamanic and hermetic summoning. I believe all the other traditions use either the shamanic or hermetic model, but your wording needs to reflect that you're not referring solely to shamans or hermetics, but to summoning elementals or summoning spirits (or however you split it up. I think I've just reinforced that it's hard to grammatically separate the two groups, even though we know that Voodoun is, mechanics-wise, shamanism.)

So basically the group pools their conjuring skill. The leader can split off a certain number of dice to augment a particular character's drain test, and the rest goes towards summoning the spirit in question, making it statistically feasible to conjure a force 8 or 10 spirit when normally such things are impossible. That makes sense. This also means that someone with charisma of 4 summoning a force 10 spirit is probably going to die unless he gets a lot of dice from the pool. That's awesome, it does allow for things like the Great Ghost Dance.

One thing worth specifying, if a member of the circle dies or goes unconscious, can the rest of the circle still draw on his contribution to the pool? If Bob the Mage contributes his 4 conjuring dice into the pool, but totally botches his drain test and his head explodes, does the party shrug and continue along with the 4 dice, or does the leader grumble that he should have dedicated 3 of those dice back to helping Bob overcome the drain so he'd at least have 1 die to contribute towards the actual conjuring? I can see advantages either way.

If you say dead members contribute nothing, you have to plan it out a lot more tactically, figuring out how much punishment you can expect the members to suffer before they drop out. In other words, with Bob, you'd take his 4 dice and give him 3 back, figuring it's better knowing he'll contribute 1 die than knowing he'll just die and leave a mess. On the other hand, it's cool to say "oh, poor Bob, he gave the ultimate sacrifice, but his death wasn't in vain."

Yes really needs re-writing for a rule book. Forums are, well occasionally, forgiving medium.

Am reticent to change the drain codes anymore because it really changes the maths and the balance of the power. Big special rituals I think should be big and er special.

As to wether a conjurer still adds dice if they die, the answer is yes. As long as the leader is fine the ritual will complete. You have to trust the ritual leader and check their rep so you know if the last group all died.

Ok, I've had time to think more on this. My big question ended up being 'why?' Why Ritual Conjure? I have friends that Ritual Sorcery alot so that they can have a sustained spell (each die not used is a multiplier for hours the spell is sustained). I've seen corps use Ritual Sorcery to locate and pay-back someone long-distance. All Ritual Conjuring seems to do is give more dice, and thus, possibly more services. If you're not wanting to reduce drain, the 'balance' is already off. You're not really going to get a more powerful spirit, unless you're wanting a Force 11 to 16ish spirit, and even then, would need a huge ass team to make it plausable. You might get more successes, but at what risk?

There's no way I'd be on the 'team' of this sort of ritual. I'm either the leader getting all those succeeses, or I'm not doing it. However, my own suggestion defeats the purpose of having multiple participants as well. I think the best way to 'balance' it is to reduce drain by 1 per additional hour, up to the number of ritual members who are not the leader.

Don't forget that Balance is only a factor for players, the corps summon whatever fits the story (see the spirits that Denver summoned to stop GhostWalker). How many games have more than 3 people of the same tradition on a team?

But, I still think it needs something more. I'm wanting to say that, much like the sustaining of a spell via holding back dice in ritual sorcery, we should allow holding back dice to gain extra services, but at that point I see a potential for balance breakage. After all, that's the equivalent of saying for every dice you set aside, you get a free success. Still, there has to be something more I think.

The main thing I don't like is that it seems pretty deadly in drain terms, so I wouldn't do it either, like Sphynx, unless all characters were marginally protected from drain.

Sure, maybe a group would risk such awful drain to conjure something unprecedented even by a high initiate, say a force 8 great form spirit, but the thing a magical group would be to summon a fairly normal spirit, with very little drain. Also for a team of magicians who want to carry some spirits with them to help on a tough run to more easily crank out a bunch of spirits to assign to each magician, and make it easier to stage down the drain.

Also, this is only really helpful to Shamans if they go for Great Form spirits, because of the whole tricky domain issue.

The additional dice can all be shifted into drain resistance if that is what is wanted, essentialy giving the effects of a spirit focus or an additional spirit focus in some cases, if we included drain reduction then the truely huge game breaking summoning occures. Read futher up the thread for how silly this can be.
It is possible for team members to hold back dice just for themselves so drain won't be as dangerous personaly if they don't trust the leader.
Ritual sorcery does something sorcery carn't but ritual conjureing allows for more successes, a bigger spirit or a safer summoning depending on how you alot your dice.
My main aim was to have a balanced power that explains how corp mages/ tribal shamens bind big spirits without being magical powerhouses.
Hence more time to reduce strain.
For the summoning of great form spirits this is especially helpful because your less likely to fall over with higher end spirits (Force 5-6)

As to wether this is useful for shamans that depends on the spirit they choose. If your in a city a city spirit seems a good bet, or a sky spirit good for anywhere out doors. On the sea choose a sea spirit etc

It has just occurred to me that in the great ghost dance people did die willing to power the ritual. So both possible blood magic (sacrificing?) and possible shamans dying from drain.

Had a though for drain reduction that isn't to game breaking, the assigned drain resistance dice count count as power foci for magic stat?

How about this.... For each additional member of the Ritual team, those who are not the Leader, 1 dice may be put into raising the Leader's Charisma for the purpose of resisting Drain (a Convent of magi can be a bit more... influential... in convincing the Spirit to not fight the summoning). Therefore a Ritual team of 3 led by a Charisma: 5 Ritual Leader would be treated as if the Ritual Leader had an effective Charisma of 7 for the purpose of resisting drain.

This does two important things.

1) Still causes the potential death for summoning too high a spirit, while reducing the chance of death due to a 'normal' Charisma and ungodly magic rating. Instead of just going for a Force 12, They'll likely go for Charisma + addtional members (Charisma-6 with 3 members is a nice Force 9 for Moderate Physical damage for the Grade 2 Initiate, whereas the same scenario, trying to go for that Force 15 will kill someone...)

2) Doesn't mess up the problem of doing a 1-person Ritual and it being better than a normal Conjuring.

Good idea. As you have pointed out though currently every other member would be facing deadly drain for the force 9 spirit. So it would have to apply across the board.

So why are we resisting Physical drain? Is it because ritual conjuring connects you to the astral?

Because if the Force of the Spirit is higher than your Magic, the drain becomes Physical instead of Stun, as per the rules.

And Pendaric, I think only the Leader's Charisma should be taken into account. Everyone's individual Magic rating should decide the Type of damage, but the non-leader's Charismas shouldn't matter at all.

As an aside, I'm going to completely disagree with Sphynx and Psycho. There is no reason to make ritual conjuring something meant for small groups of PCs. Part of the fun of Shadowrun (for me) is that I can play a group of runners, mercs, corpers, etc. So the fact that this doesn't give benefits to a small group of runners shouldn't be TOO much of a concern, IMO.

The only thing I think ritual conjuring should be able to do is allow a group to conjure up a very high level (12+) spirit while losing less than 10% of say a 8 person circle, and that a larger group has a reasonable chance of summoning up a larger spirit (the Great Ghost Dance conjured up an insanely large spirit, but had hundreds of people dancing. What's the force of their spirit? 20? 30? How many dice do you need to be able to roll a 30, and how many people would survive the encounter?)

I was thinking about whether it should be possible to reduce the drain to 2D. At first I'd say no, but it occurs to me that with 2D damage and a large enough group, some people still will die. I'd have to think on that more. I would add in drain-reduction rules with caution, and I would not, not put in any rules that significantly reduce the damage Level.

Has this mechanic been used with high force, large group situations? High force low group? Large group low force? Ultimately, testing is going to be what really makes or breaks the design.

Err... How is that disagreeing with me?!?

I never claimed it should be valuable to a 'small' team, I just want it to be something more than a basic conjuring. Ritual Sorcery actually offers more options than to just cast a spell, Ritual Conjuring should also. There has to be sufficient cause to 'Ritual' that conjuring than just attempt a conjuring. At least with the Charisma option, there's a reason to Ritual it.

I have play tested the rules as is for balance. You can get high force spirits (12-14) if don't mind lossing people, often a lot of people. You do start to struggle with force 15 to 17 because of the drain and success ratio. But if you dont mind few successes and high body count its doable. Meaning the leader walks way if their lucky from a large group.
Sphynx idea has merit but I now need to sit down and do the math 'groan'.
I orginaly set this as a thing that corp mages with charisma 3 did to get big spirits and great form spirits.

Ok I have done the math. There is no way to reduce the drain code without ritual conjuring becoming the sick beast of the mega spirit.
I ran the numbers up to a sixty strong group and didn't include karma. I tried number of members, leaders iniate grade and total intiate grades as limiting factor, all lead to over the top results. Very power gamer heaven.
However I tried this rule which isn't to bad but with reservations.
For every three members of the ritual group increase each members effective magic for this summoning purposes by one.
This led to a 30 strong group reliably summoning a force 12 spirit and a 60 strong group reliably summoning a force 16, with no deaths. (headaches and unconsciousness but no deaths) This was because more dice could be put towards the leader's rolls.

As to my reservations, the power of spirits is a relative scale. Being able to summon a force 8 spirit beats a force 7 spirit, force 9 beats force 8 etc if the maximum you can safely summon is more than your enemy you win. By making higher viable we redifine the limits. Hell once in the six world Any force spirit beat the oppersition.
I can not think of anything more to do with ritual conjuring that does not break it.

I got to thinking about this last night and came to a sudden realization. The reason there is no such thing as Ritual Conjuring in the books is because most Conjuring is a ritual already. Watchers are the non-ritual form of Conjuring. If you want to summon a Force 30 Nature Spirit to wreak havoc, you keep everyone distracted from you by having your tribes do some great Ghost Dance while the leading Shamans go into a wigwam and do an Astral Quest to the native realm of that type of spirit, and bind some powerful spirit via name. Not everyone survives the quest, but you bring back the spirit. It's alot more than a single TN to summon, and a drain based on Magic and Charisma.

Now, if someone came up with something interesting that a new Ritual Conjuring can do (such as how Ritual Sorcery can sustain spells on its own, or locate someone, or be cast long-distance), other than making the resisting of drain easier, I could see it being interesting. As-is though, the only advantage currently is if you get a ton of people, and summon a slightly larger than norm spirit. And as a player, I'd rather just summon ten times as many spirits that are half the force.

One interesting idea is the ability to summon something -else-. I mean, when GhostWalker attacked Denver, what exactly were those spirit things he was battling. Not Nature Spirits, Elementals, or Elemental Spirits. They were something else. Maybe that's where the focus should be. Spirits that are a typical force, but near-horror in concept, from a more -strange- plane. Unique powers like Astral Armour, Astral Net, etc. Things that can take days, not hours, to summon, and aren't particularly useful unless you're battling dragons or exploding volcanos. Unable to do any 'basic' spirit services such as concealability, search, spell sustaining, etc. Things that you have to agree with, not that owe you services. Or, more simply, owe you only 1 service regardless of successes, but more likely are interested in working with you out of self-interest (demons?)

Just some random ideas there, nothing I'd actually recommend, but more along the lines of where I think a more ritualistic conjuring should be heading.

Ok, try this.

Ritual conjuring allows the conjurer to conjure Shedim, Nomads, Wraiths, Baba Yagas, Bean Sidhes, Broken Bows, Corpselights, Domovois, Kings Frost, Tungaks, and/or unchained Spectres.

As these spirits have not yet established a standardized conjure-response arrangement with metahumanity, the conjurer needs a ritual, dangerous astral quest, and often some exotic oddities from some part of earth.

Examples: A broken bow would require some dirt from the site of the witchcraft in question. A nomad's ritual requires the brutal, torturous killing of a metahuman before the ritual can be completed. A domovoi only would require a location defined and a miniture room in that house. A tungak would require a culture of a disease, preferably thriving in a living metahuman host.

This could also be used to conjure other spirits of types that you could not normally conjure, but with the same "research, astral quest, ritual" base combination.

I feel rather than stat's for these kinda of rituals they should remain more roleplay affairs.
But as I said am out of ideas, i have gone round all the concepts i can think of: multiple summoning, distance summoning, and the above seems the most balanced and valid. The ability to have a force 12 guardian elemental in stead of two force six ones seems enough. I see ritual conjuring as an edge to magical groups.