Is it possible to cast spells above 9th level in a crystal sphere that is not under the influence of Mystra?

Question

Mystra's Ban was a decree that the goddess Mystra made about the mortal use of powerful magic.

In -339 DR Karsus seizes Mystryl's powers through the casting of Karsus's Avatar, but they are too great for him to control and the Weave fails, causing Netheril's floating cities to fall to the ground. Mystryl sacrifices herself to save the Weave. She instantly reincarnates as Mystra and changes the rules for magic users.

From my understanding of the lore every deity has absolute power only in the crystal spheres where he/she is worshipped.

So, has Mystra banned 10th, 11th and 12th spell from all the multiverse? Does this mean that she is the only goddess who protects magic in all the planes of existence?

Answer 1

The lore of the Forgotten Realms has often been written as though the Realms were all that was; it does not appear that many Realms authors defaulted to seeing Toril as just one world among many. Thus, there are many lore inconsistencies, particularly when it comes to Mystra’s control of magic, when we compare Forgotten Realms lore and wider multiverse lore. To wit, within the Forgotten Realms, Mystra is among the most powerful of gods, and controls all magic for all creatures great and small.¹ Outside of the Forgotten Realms, Mystra is a minor player from a single sphere who doesn’t control much of anything outside it.

So you ultimately have to take a stance on this meta situation before you can start to untangle anything about this question. Are we coming from a Realms-specific mindset, where Mystra is a chief god? Or are we coming from the multiverse, from a Planescape mindset, where Toril is just one world of no special note, and being a god found only there, Mystra is thus a relatively minor player?

On the subject of the end of “true” 10th-level and higher spells, for instance, we have two conflicting accounts. The multiverse-centric version has all of the changes from 2e to 3e caused by the events of Die, Vecna, Die!. Here, the lich Vecna gets himself misted by Ravenloft, and becomes a Darklord of Cavitius, one of the domains in the Demiplane of Dread. However, he schemes to absorb the divine power of rival and demigod Iuz, which causes Ravenloft to reflexively boot him out, and he manages to set things just right so that he is booted out of Ravenloft into Sigil while still mid-apotheosis. He uses this loophole to get around the Lady of Pain’s ban on gods in Sigil, and then attempts to take Sigil for himself as part of a wider scheme to take over the multiverse. Canonically, adventurers succeed in ousting him, but the damage is done, and all the changes from 2e to 3e—including the loss of true 10th-level spells—results:

Some Outer Planes drift off and are forever lost, others collide and merge, while at least one Inner Plane runs "aground" on a distant world of the Prime. Moreover, the very nature of the Prime Material Plane itself is altered. ... New realms, both near and far, are revealed, and realms never previously imagined make themselves known. Entities long thought lost emerge once more, while other creatures, both great and small, are inexplicably eradicated. Some common spells begin to work differently. The changes do not occur immediately, but instead are revealed during the subsequent months. However, one thing remains clear: Nothing will ever be the same again.

^{(Die, Vecna, Die! pg. 151)}

The problem with this story, from a Realms perspective, is that none of this has anything to do with the Realms. Vecna and Iuz were Greyhawk characters, and Sigil and the Lady of Pain are of course central to Planescape. And the Demiplane of Dread was yet another campaign setting. If this were to be the canon explanation within the Realms, it meant anyone learning about the Realms would also have to learn about all of those settings. It also meant that the grand battle between Mystra and Shar starts looking like a minor scuffle between two locals with little influence on the broader scheme of things, which is probably not really the tone Realms authors were looking for. So as a result, the 3e Forgotten Realms Campaign Setting defines an entirely new cosmology, the World Tree instead of the Great Wheel. Almost everything about the World Tree is identical to the Great Wheel, with the key difference being, quite simply, that it wasn’t the Great Wheel, and events on the Great Wheel had no influence on the World Tree (or vice versa), and thus had no influence on the Forgotten Realms. The other difference was that, although all the other planes were the nearly identical to those in the Great Wheel (per Player’s Guide to Faerûn), they didn’t connect to one another directly—you had to go through Toril, the “trunk” of the tree, in order to get from one to another. This centralized the Realms, justified the importance of its gods and other denizens, and, conveniently, replaced the central pillar of the Great Wheel: the Spire with Sigil atop it.

That meant that Die, Vecna, Die! was—kinda sorta—no longer the explanation for the edition change in the Forgotten Realms. As ZwiQ’s answer about edition transitions in the Forgotten Realms says, the late 2e FR module Cloak and Dagger establishes a timeline from 1368 DR to 1370 DR, and mentions a few things for 1371 DR onwards. The 3e Forgotten Realms Campaign Setting picks up where that left off, stating the campaign runs in 1372 DR. There is no “transition event” specified here. ZwiQ mentions Die, Vecna, Die! at this point, because at least from Planescape canon, that’s the explanation for everywhere, FR included. From an FR (only), World Tree-based, perspective, perhaps not?

So what they did instead was a ret-con. Mystra’s ban—established in the 2e module Secrets of the Magister as thoroughly detailed in illustro’s excellent answer—was changed to be more thorough than it had previously been. Where Secrets of the Magister talked about Mystra’s ban just changing the incantations and symbols for some 10th-level and higher spells so that old codexes were no longer accurate, thus forcing spellcasters to engage in an expensive and risky research and experimentation process, Lost Empires of Faerûn turns Mystra’s ban into something much more comprehensive:

Mystra banned certain high-level spells that she deemed too powerful for mortals to wield responsibly. Thus, current-day spellcasters no longer have access to true spells of 10th level and higher. Instead, access to epic magic comes via two feats—Improved Spellcasting Capacity and Epic Spellcasting—that function in very different ways.

The Improved Spellcasting Capacity feat grants spell slots above 9th, theoretically without limit. Before Mystra’s ban, powerful mages could fill these spell slots either with true spells of 10th level or higher, or with 9th-level or lower spells fortified with various metamagic feats. After Mystra’s ban, only the latter option remained available.

The Epic Spellcasting feat allows the development and casting of epic spells (spells requiring the use of the epic spell system presented in the Epic Level Handbook, cast through superior mastery of the Spellcraft skill). Mystra’s ban has never applied to epic spells, even those that duplicate the effects of 10th-level and higher spells developed before the fall of Netheril.

Epic spells did exist during the days of Netheril, but the Netherese largely abandoned their development after the discovery of the nether scrolls. During the age of Netheril, epic spells were largely the province of the Fair Folk and were thus almost exclusively associated with elven high magic. The Netherese, for their part, preferred to develop and use 10th-level and higher spells.

^{(Lost Empires of Faerûn pg. 43)}

Here we see how 3e is being handled as ret-con rather than in-world change: elven high magic always existed, but the Spellcraft skill and epic spells of the style that the Epic Level Handbook describes were new. Likewise, the mention of metamagic feats is a ret-con; those weren’t an option before 3e. Lost Empires of Faerûn describes the Realms as if things were always this way.

Anyway, later editions quietly dropped the separation of the Realms from the rest of the multiverse. Hell, for that matter, 3e and “v.3.5 revised edition” Forgotten Realms material often seemed to forget about it too. Officially, the World Tree is regarded as an alternate model of the multiverse, something mortals contrived to try to understand the planes, but which has not stood the test of time and which has largely been outcompeted by the Great Wheel model. This contrasts with 4e’s World Axis model, which—at least in FR—was treated as an actual change to the layout of the multiverse that occurred due to the Spellplague, and which was undone by the Second Sundering. Other campaign settings didn’t bother to explain why the planes were different, and post-4e have largely elected to pretend the World Axis never happened.

On the other hand, later editions have also exported a number of formerly-unique-to-the-Realms details to the wider multiverse—most importantly, the Weave, which previously did not exist outside of Realmspace. How these things work now that they’re no longer exclusive to the Realms—and how much influence Realms deities have over these things outside of the Realms—is not explained at all, however.

Is it possible to cast spells above 9th level in a crystal sphere that is not under the influence of Mystra?

Originally—in 2e—yes, this was true. But then Mystra’s ban wasn’t absolute in 2e FR, either.

After the events of Die, Vecna, Die! changed the way things worked from 2e to 3e—including the removal of “true” 10th-level or higher spells—it became impossible to use true 10th-level or higher spells everywhere in the multiverse. However, within FR, the explanation for this may not be Die, Vecna, Die!, but rather a ret-con of Mystra’s ban making it more absolute.

1. _{Ignoring, for the moment, Shar’s Shadow Weave.}

Answer 2

Even in the Forgotten Realms, as of 2nd edition, "post-ban", lore wise 10th level spells are still possible.

As part of AD&D 2nd edition, the accessory module Secrets of the Magister, written by Ed Greenwood (creator of FR), was released. Within this book, there is specific additional lore on how the ban on 10th level spells was implemented by Mystra.

Specifically the Magisterial Magic > Forbidden Spells section has the following lore:

After the folly of Karsus (the Netherese archwizard who aspired to godhood, uncaring of the effects of his spell- driven ascendance, and succeeded in both disrupting the Weave and bringing about the passing of the goddess Mystryl), the newly ascended Mystra stripped mortals of the ability to handle specific 10th-level spells. She did this by altering their enchantments to make them both inoperative and incomprehensible to the Netherese alive at the time (in other words, all of the recorded incantations could no longer "take hold of the Weave at all, and hence the spells simply would not work). Mystra also altered a few of the symbols and glyphs of these incantations to make them injurious to the minds of beings attempting to memorize them or read and tinker with them. History incorrectly records this as changing humans to make the use of such magic beyond their grasp, or changing the nature of magic to make spells of greater than 9th level unintelligible to humans, because that is what the goddess wanted mortals to believe (to keep strivings after such forbidden spells to a minimum, and the waste of spellcasters' lives and efforts small).

So it wasn't that 10th level and above spells were no longer possible, but that pre-existing True Dweomers were altered so they wouldn't work. To the people at the time, this would have seemed like 10th level spells were no longer possible...so why would they try to research any more? The only conclusion that mortal spellcasters could conclude is that 10th level and above are no longer possible.

It goes on to specifically say:

It is possible, in the Realms of today, to research True Dweomers and even new 9th-level spells to achieve specific severely limited ends that resemble parts of what a 10th-level spell could achieve.

So, even though mortals believe that these spells are no longer possible, they are, if you are willing to put in the leg work to do the additional research (which no one has).

Additionally, the alterations Mystra made to existing 10th level and above spells are such that:

It is also possible for mortal spellcasters alive today to use any written 10th-level magic they may find, with the following warnings:

• Attempts to cast such magic will always fail the first time.
• All castings will be failures if the caster has less than 18 Intelligence and 16 Wisdom, and is or less than 20th level.
• All castings result in unintended wild magic results if the caster does not have the assistance of a second spellcaster (of at least 18th level and 18 Intelligence) who uses another spell or spells to link his or her will, mind, and life energy to the principal caster, as an "anchor." Minor (or deliberate) discord among casters prevents the effective use of a third or additional spellcasters joining the anchor to make the spell more likely to take precise effect.
• All casting attempts are very likely (85% chance) to result in a loss of one experience level on the part of all casters involved, and will always cause the loss of 2d6 hit points and 1d4 other memorized spells (if any) from each of them
• All casting attempts attract the attention of both Mystra and Azuth. If they deem the casting to be for purely personal ends, or to have the death or destruction of a rival mage or magical items as their primary goal, or to be in support of any tyranny or oppressive authority (in other words, to work against the free and individualistic ongoing development of magic use across Faerûn), they will cause the end result to be feeblemindedness of all the casters involved and the instant disappearance of the written spell.

Essentially you have to be really persistent to attempt to use an already existing 10th level spell...and you have to do it at least twice to get it to work. Even if you do get it to work there is a significantly good chance you get royally messed up when you are successful.

Finally the section ends with the following note about how restricted this information is:

The information related in this section is largely secret, but the points about the possibility of researching powerful magic, and the restrictions on the casting of found 10th-level spells, will be slowly and partially shared (through visions sent by Mystra) with any player character who prays to Azuth, Mystra, Oghma, or Savras for answers or guidance on this topic or by high-ranking clergy of Azuth, Mystra, or Savras who are directly asked about such things by any mage (such is Mystra's commandment).

Answer 3

Mystra's Ban only explains why high level spells are limited within Forgotten Realms

There's no specific reason given for why higher-level spells do, or do not, exist in other realms in general. There's no reason to assume Mystra had a hand in it; for all we know Mystryl was just an unusually lax goddess of magic (she was canonically Chaotic Neutral alignment in 2E after all), allowing higher level magic than any sane god/goddess of magic allows anywhere else, and Mystra was just reverting to the multiversal standard followed everywhere else.

It's clear that higher level spells do exist elsewhere (e.g. Dark Sun, although that's a poor comparison, since it's such an isolated setting, with no gods at all), so clearly her purview isn't absolute, and there's no reason to believe that Mystra, alone among the gods of the Abeir-Toril sphere, possesses powers over magic everywhere.

Answer 4

10+ level spells might be a unique feature of the Realms

About Mystra's ban

There are already excellent answers posted, stating clearly that Mystra is only a power of the Forgotten Realms setting and she has no jurisdiction on how magic runs in the rest of the multiverse. This is also discussed under other questions such as: Why does arcane magic work outside Toril?

Beyond level 9 in "special" ways

I want to highlight that within the D&D lore, AFAIK there are no official pure-magic "ordinary" 10th, 11th, 12th level spells beyond those that were published during the AD&D 2e Forgotten Realms products. Campaign neutral books describe "true dweomers" (Dungeon Master Option: High-Level Campaigns, 2nd edition precursor for epic spells), "quest spells" (Tome of Magic) and "epic spells" (3rd edition SRD). The Birthright setting had War Magic, Battle Spells and Realm Spells. Forgotten Realms had "elven high magic" with unique rules. Darksun had 8th, 9th and 10th level "psionic enchantments".

Some of these were mechanically treated as 10th-level spells for the purposes of calculating saving throws, spell resistance, etc. For example, 3.5e SRD states:

Epic spells have no fixed level. However, for purposes of Concentration checks, spell resistance, and other possible situations where spell level is important, epic spells are all treated as if they were 10th-level spells.

Yet, these were not "ordinary" 10+ level spells that spellcasters would naturally get access to as they gained levels. They had special rules like requiring long preparation times, collaboration of multiple casters, unique circumstances, feats, skill checks, etc. The closest we got to ordinary spell casting was Darksun's "psionic enhancements", ie. 10th level wizard and 8th, 9th, 10th level cleric spells that were described in the Dragon Kings. Quoting from page 7:

Beyond the horizons of routine magic are whole seas of power that cannot be tapped naturally. The unaided mind, regardless of intelligence, cannot comprehend, let alone command, such tremendous energy. But psionics can "tune" the mind for greater mastery of magic.

So the psionic enhancements were indeed spells, but they could only be wielded by spellcasters who had reached level 20 and were also 20th-level psionicists at the same time and were in the process of turning into advanced beings. These spells also had special preparation times measured in days.

Mystryl as facilitator for going beyond the 9th

In short, "ordinary", single-caster, pure-magic spells of 10th level and higher appear to have been granted by Mystryl/Mystra only. It can be argued that it was her who actively facilitated these spells and made them accessible to the mortals. In the FR lore, Mystra has occasionally been described as being the Weave herself, not just its maintainer.

As an added circumstantial evidence, here is a quote from the description of the 10th level spell Valdick's Spheresail (Netheril: Encyclopedia Arcana, page 12, emphasis added):

Unlike spelljamming helms, which converted magical energy into motive force, the spheresail gained its power from one of two sources, depending upon where it was being used. Within a crystal sphere, the spell dipped directly into the magical forces of the goddess Mystryl and converted this raw power into motion‚ giving the spelljamming craft great speed ...

Conclusion

In summary:

• Mystra's ban applies only to the Realms, as she has no say on how arcane magic works outside of the Realmspace.
• It is only in the Realms setting that 11th and 12th level spells are ever known to have been cast. And only the Realms setting has had 10th level spells that were "readily" accessible to spellcasters of high enough level.
• In non-Realms settings, the DMs should perhaps construct the question differently: Instead of "are they banned?", they should ask "are they possible at all, if so what should be the mechanism?".