Is there any way to reliably destroy a level of a regio? I'm familiar with the spell Stripping the Superfluous Realities (RoP:M p14), but it is a ridiculous, haphazard effect - essentially, you attempt to force a botch. Between "Cautious Sorcerer" and the Gold Cord binding a familiar, many magi have a very small chance of a botch, even if the spell adds botch dice. Even if you use Divine vis and double the botch dice, your odds are small and you are in the odd circumstance of hoping for multiple zeroes on your dice.
Does any spell or effect cause the desired outcome--destroying a layer of a regio--as a result of being good at spellcasting, or at least clever? Adding magnitudes, including some prerequisite, identifying and destroying the tethers first, whatever? Attempting to make the circumstances as difficult as possible to eke out a few more botch dice is absurd. (Alright, what if you were blind drunk, hopping on one leg, and children pelt you with snowballs? That has to be worth an extra die or two, right?)
It is not the magi who are rolling, but rather the regio/aura itself. So Cautious Sorcerer and the familiar Gold Cord do not come into play here. They affect the spellcasting roll, whereas Stripping the Superfluous Reality affects the (and forces an immediate) roll on the Aura Weakening Table.
Messing around with auras is not something that should be either easy or reliable.
p 7 of RoP:M
"Any effect that reliably manipulates a Magic aura should probably require at least a Major Breakthrough or an Mystery initiation."
I guess that explain why there are no cannon ways to destroy a regio layer: it is left to each Saga and troupe to engineer their own doomsday machine.
I might have missed it, but I did not find either what happens when a regio layer disappears. It should not go smoothly, and inhabitants might be for a rough ride, and probably some angry payback.
Nevertheless, the chart only allows removing a layer temporarily, for a year at most. (If the text doesn't explicitly say that the effect is permanent, and deleting a layer isn't listed as permanent, then it's temporary.) And you can't get rid of the last layer, just rearrange the furniture. (If you destroy the only level, a new level will be created, though any contents on the mundane level will be deposited in the new layer. Woo. Hoo.) I'm OK with it being hard--that leads to stories. But allowing a minor chance of creating a layer, with no balancing chance of removing one is not OK.
The character wants to get rid of a multi-layer infernal regio. The occupants, including the diabolists, are gone. But the sore on the side of creation remains. Is that really going to stay there, barring a literal deus ex machina? Lobbing in a relic like the Holy Grenade is an unsatisfactory end to the arc.
First of all you are referencing rules for magic regios to deal with infernal regios, which means you are dealing with the wrong section altogether. Infernal regios are dealt with in ROP:I, and there are several ways to easily be rid of them- largely involving establishing a divine aura over them. The Gruagratchen can also deplete infernal auras (and by implication regios) with great difficulty. Incompetant diabolists might do the same trying to raise the aura, but I definitely would not want to depend on that method.
Well, upon further research, the only option I can find is the second most useless mystery in the MRE: Hermetic Architecture. (I'm pretty sure Periapt takes first place, but YMMV.) If you repeatedly halve the size of the regio until it gets to 1 pace or less, it most likely go away. (I'm basing that on the Closed Privacy of the Enchanted Regio, which shrinks the boundary until it vanishes at 1 pace.)
Yes, I understand. That's part of the "hard" I was including, it would require some research, some quests, and possibly some breakthroughs. Establishing a higher divine aura will only suppress and eventually reduce an infernal aura, not a regio. It simply will be harder to access if the infernal aura on the mundane level hits 0. And that depends on the infernal aura remaining without naughty children supporting and strengthening it. If it's in active use, it isn't going to reduce in level.
The Muspelli can alter an existing aura, specifically including an infernal aura, which makes them a good source of research, but once again they don't explicitly affect a regio, just the base aura. And, of course, they're mostly mad/evil, so they are not terribly likely to cooperate without a serious favor in return.
The Zoroastrians also have a moderately vague new guideline for the Wonders holy power (TCTC p.97), but being vague it would require a GM call and discussion with the troupe.
According to RoP:I infernal regios are areas where the divine is completely absent, so it seems to me that any level of consecration of an infernal regio will destroy it (or count as heresy and trying to defy the will of God, so there are risks).
Regios are also described as being a part of hell itself which reaches out towards the mundane realm, so cutting off access may be as good as destroying them from a game perspective.
Several people have demonstrated that each Realm seems to have its own set of rules, the great unification of the four powers has not been done.
So probably to be able to use a similar spell from one Realm to affect a regio from another Realm, Confluence of the Realms (p14, Legends of Hermes) would be required.
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