What kind of spell is needed to cure insanity caused by a spell? Assuming now that character was not mentally ill before he got targeted by the spell.
If possible (sometimes perdo spells destroy things so utterly they can't be put back together), it would be creo mentem.
That's to cure as before. You might be able to get to a useful but alternate result (possibly if the mind is too far gone for creo to help) by "rearranging" the mind with rego or muto mentem.
What would be the base level for those spells?
Really need to know what the spell effect was that caused it, and how. Was it terror, or direct brain damage, or a cognition impairment effect, etc? Creo perdo rego?
I'd say it's almost certainly Creo to restore function but there might be an edge case for Muto.
It was the 72 lvl version from Black Whisper, page 151 ArM5 . Perdo Mentem
Black Whisper has a duration of Moon, so after that effect expires the target would return to normal (ish). For the duration the target's mind is not able to to function properly. They'll have some very bad memories, and probably couldn't be depended on to accurately remember anything from the spell's duration anyway. The spell is Moon and not Momentary, the spell design has paid for the effect to expire. It could have been written as Momentary, which would be lower level and have the same effect, as it's Perdo!
Suggest that to recover from that insanity style is the same base difficulty, Creo Mentem 15, or perhaps Creo Mentum 20 at the outside. CrCo15 is the same as a Corpus minor aging crisis, and CrCo20 is a disease or malady, or a stronger crisis. So I'd go with Creo Mentum base 15.
The CrMe effect could also be cast during the PeMe spell duration and would alleviate the effect while the Creo effect continued. If the two spells have the same base effect then the one with the higher Penetration wins? Or does the Creo effect need to be higher.. not sure.
aside - As written Black Whisper feels more like Rego, and as a Rego effect it feels like a ReMe20 effect.
What do you mean 72 lvl version?
4th ed had a Creo Mentem General Ritual 'Return of Mental Lucidity' which undid the effects of a (non-fatal) malign Mentem spell. Target level was the level of the malign Mentem spell. Range Touch. In 5th ed terms this would be a R. Touch Momentary Ritual.
5th ed Creo mentem guidelines mentions healing minds in the description yet there are no guidelines or example spells for this. Comparing Mentem with Corpus a Base 20 heals aftereffects of disease, poison etc. Perhaps a mental healing spell - Ritual of course - should have a Base equal to the Base of the malign Mentem spell? Is it fair to dock the healing ritual added cost because of a needlessly overpowered Perdo Mentem spell? I mean, a really nasty specialist could design a PeMe as Sight or even Arcane and T:Group for a high level. I know this attitude is detrimental to Penetration, but the target need not possess MR...
The lowest possible level of a malign Mentem spell would be at R:Touch, same as the healing Ritual. Well, technically R:Personal is possible, but let's just write that off as impractical.
So for a 5th ed Black Whisper at base 15 a level 20 CrMe Touch/Mom/Ind - Ritual would do the trick....That does seem sort of easy. Using the full level of 40 does seem excessive though. Note that Black Whisper is D:Moon so the effects wears off after a month at the most.
So it just occurred to me that Winds of Mundane Silence or even better Unraveling the Fabric of Mentem is an easier fix to this. Perdo Mentem does not seem to have tghe same permanency as other Perdo spells, like PeCo.
Perdo mentem does seem a lot like perdo imaginem in that something "destroyed" is mostly suppressed; however, unlike perdo imaginem, there seems to logically be a point where a perdo mentem spell can blow away enough memory that there isn't enough left to recreate it from one's own other memories.
I would say the same is (roughly) true with sanity, that most people are generally sane, so any insanity would be temporary unless the PeMe effect really warped the person or destroyed something that kept the person sane.
I also agree that, for a persistent spell, a PeVi would be a better choice for undoing whatever was done than a counterbalancing Creo spell.
I'd go with the "use the CrCo guidelines for healing" idea. That seems to be what the authors have done for other instances of 'healing'. For example, repairing items using CrHe or CrTe are essentially "heal light wound" spells.
Suppressing an emotion with Perdo makes sense as a temporary effect. However PeMe guidelines also indicate that the destruction can be permanent, particularly with memories or basic brain function. It seems it is both, which feels right to me in terms of the tone of the spells in core.
Sure but IIRC there are no examples of PeMe spells working this way, so we're all grasping in the dark here. I agree it makes sense, but it is not something I have considered.
Breaking the Captains Baton, from MoH is a permanent PeMe effect, p50. That might be memory not sanity, but I think it holds sway.
This question came up in our saga, and we found this reference:
Tales of Mythic Europe makes reference to curing Olivia of her insanity (p118). The text makes reference to a CrMe ritual that is the equivalent of healing an incapacitating wound to restore sanity, which would in turn allow the magi to get something resembling sense out of the ghost.
This makes it's a CrMe 35 ritual (base 30, r: touch).