Right, I'm making up my own character now, and he has the Lycanthrope Flaw, which is, of course, part of a larger story arc.
I'm thinking about an invested item that will hinder the transformation, or restrain the beast as much as possible. This item is a part of the big story with this character, so what kind of magical effect should be used to hinder the transformation or restrain the beast after he has transformed?
Any ideas? I guess it would be either Rego Corpus or Rego Animal?
Eirik
Id say an Item with a continuous InAn animal effect much like the one which was discussed not long back in another thread pertaining to a change into a bird if I recall rightly. Have it detect when the character is no longer human and then trigger an effect which effectively paralyzes the beast form, some high-level (or high penetration if the werebeast has MR) ReAn effect.
Depending on your lab total you could even try a MuAn(Te) effect to turn the werebeast to stone for Sun Duration. That would lock it down nicely.
Or of course just go the classic route and have your character voluntarily lock himself in a cage surrounded by an inward targetted circular ward against beasts just before he/she is going to experience the transformation.
This latter presupposes that your character knows he/she suffers from Lycanthropy.
Something like:
Bodily Prison of the Were Form
ReAn - Level (28?)*
*depends on whether additional levels of penetration are needed to overcome MR
R: Touch D: Sun T: Ind
This effect completely immobilizes a were creature for Sun Duration.
Base 5, +1 Touch, +2 Sun, +1 size +3 levels linked trigger (linked to InAn effect to detect change from human to Were form).
What an ace idea. How about a pair of silver shackles (nice material/form bonuses there) that have a perdo vim effect preventing that particular magic from taking effect (with it being focused on a particular kind of magic it shouldn't be very hard to make.
Does your magi sprout fangs n' fur at a certain time, such as full moon?
Love the image, its full moon and before the sun goes down the magi heads into the sturdy cell in his tower, commands his apprentice to lock him into his magic silver shackles and spends the night there hoping they keep him as a human. Very mythic.
I had a lycanthrope in one of my games and I had his beastial alter ego slowly become more clever and powerful (increased might) over time. There came a point where the protections that had worked in the past no longer sufficed to keep the beast controlled.
Yes love the image too. However, Gribble, no hermetic magic, IMO could prevent the change to Were form as it is not a magical effect but a supernatural one. It certainly isnt any sort of Vim effect.
Best solution is imprisonment (cage, shackles, paralysis, transmutation to inanimate form, etc.).
It's important to have an item that the magus can bring with him on journeys (shackles, for example).
The main question would be what kind of effect that could calm or restrain the magus in wolf form. The item could shange shape with the magus. Maybe a leather collar with silver studs on it? 
Oh, and he knows he's a lycanthrope. It was a "gift" from his rather psychotic and experimental-minded master.
E.
To calm an animal would be 1 magnitude lower than the suggested effect I posted above, to make an animal completely passive, 1 magnitude higher.
Much less fumbling about with shackles and such for use in travel if you just enchant it into a ring or pendant that he would always wear. Safest of course would be to simply paralyze him totally at the level I already suggested, then no worries about the beastial form eventually learning to overcome any calming effect.
Hi, we had a similar problem in our saga. The wife of the nobleman Olaf who legally owns the grounds of the convent is a werewolf of Pomerania. They us the lock-up-method during full moon. Olaf was quite annoying as he imposed high taxes on our income. However, a character with second sight sensed something intimidating about his wife so the couple was investigated magically and with mundane means. This finally revealed the true nature of the noblewomen Hedwig. The Characters had several different ways of reacting towards this: Kill the beast, kill both, blackmail them but went for helping them.
Momentariliy one of our magi is improving his arts so he can finally craft an item to suppress the transformation.
As Hedwig is a non-player charachter I have no problems revoming her major flaw. I might not have been so generous if a player's character wanted to get rid of his flaw.
However, here is the solution we came up with..
Amulet to turn Werewolf into Human
Mu An (Req: Co, no increase of magnitudes, Me +1 magnitude)
Base level: 10 (turn animal into human)
Requisite: Mentem: +1 magnitude (to suppress the aggression)
Range: Touch: +1 magnitude
Duration: Sun: +2 magnitudes
Target: Individual: +0 magnitudes
End level of a spell: 30
Environmental trigger: +3 levels (triggers at sunrise and sunset, so a constant effect is produced)
2 uses/day: +1 level
Penetration of 30: 15 levels
End level of the device: 49 (!!!)
About the penetration: Hedwig has a magic might of 20, thus you have at least to reach penetration of 21. However, penetration of a device is reduced by the realm interaction chart. So a divine aura of 3 subtracts 9 points of the penetration total. Auras above three are seldom encountered outside a church so a penetration total of 30 should be sufficient.
Note that the aura would also alter the werewolf's MR itself, so assuming the effect is Magical no further increase in Penetration is actually necessary... but it doesn't hurt to pack in some, just in case.
Doesn't this just mean however that the spell will be cast at sunrise and sunset only, and that if the lycanthrope is in human form at this point the spell won't have any effect.
i.e. At sunset, when the spell is cast, Hedwig is still in human form, and the spell has no effect. Then, at midnight (or when the full moon shows) Hedwig is turned into a werewolf, and remains in her wolf form until the spell is cast again at sunrise. By this time of course the damage will have been done, and she will naturally have returned to her human form anyway. In other words the magical effect in the item is useless.
It would seem the best trigger would be "when in animal form" or something like that, yes.
Which would require a wholly separate Intellego effect for the device to sense when the shift to animal form was occuring and a "linked" trigger in the above effect linked to the Intellego effect (rather than an environmental trigger) in order to activate.
Maybe one could device a spell that specifies that the target stays in human form for the duration of the spell, rather than being changed from animal form? Of course this would put the target under a constant magical effect, and thus cause warping.
Exactly. That would be an effective, but not efficient solution.
I guess that depends on how much you really care for the target person. If warping is a side effect the magi are willing to ignore, it would surely take some time before the victim realised the side effects. This could make for some interesting roleplay and plot turns as well. 
Perhaps, but it would also potentially give the device-maker a bad rep for inefficient and harmful devices and quite possibly add further cause against the Order and magic from mundane society and maybe even the Church depending on how prominent a member of society the user happened to be.
Far more discreet and diplomatic to make devices as efficient as possible IMO.
I don't believe so.
The spell has a duration of Sun, meaning that its effects linger despite the target not being appropriate at the time of casting. The individual would still be under the effects of the spell, its just that as long as they remained human the spell wouldn't affect them.
As-designed this causing Warping, what with its constant effect on the Touched target.
If the transformation is triggered by something reliable (typically monthly astrological effects) the environmental trigger can just be set to that and the duration to Sun and you only need 1 use/day and no need for complicated triggers.
You're going to need a Rego requisite to alter her mental state - the Muto component is insufficient, I think. With the +1 magnitude for Mentem already in there you do get her to remember her time as an animal for free (based on MuMe guidelines). Adding in the ability to control her mind though is a separate +1 magnitude for Rego.
Even still, she zonks out during the transformation. Considering the alternative that's not so bad, but she's still a calm animal in a human body for the duration of her alteration.
It might be easier to have the ReMe effect as separate, depending on Lab Totals.
You'd have the MuAn effect (lvl 43: base 10, +1 Touch, +2 Sun; +3 trigger, +0 1 use/day, +15 Penetration) and a ReMe effect (lvl 38: base 5, +1 Touch, +2 Sun; +0 1 use/day, +15 Penetration). As separate effects she wouldn't remember her night, though.
To BoXer:
Of course you are right in all those respects, but not all magi are as discreet at they should be, and a reckless magus might not bother. Or maybe he doesn't have the necessary Intellego skill for creating the detection/trigger bit.
Anyway, does anyone have an idea about how such a "stay in human form" spell would be formulated? And if it would at all be possible to prevent the transformation through hermetic magic?
What sort of effect is the transformation of a lycanthrope? Can it be an infernal curse in some instances?
I would have to disagree with this interpretation.
The spell does not make sense, in my eyes, unless the condition it is designed to alter is already present at the time of casting. The condition would have to be met for the effect of the spell to manifest itself, and there would be no lingering effects as long as it didn't manifest itself in the first place.
Anyone else got any thoughts on this?
The spell would be a MuAn(Co) spell IMO since you are seeking to revert back from animal to human form.
Forestalling the Beastial Form
MuAn(Co)(Me) Level 30 (not including effect trigger, linked or otherwise)
Reverses the effects of lyncanthropic transformation and prevents recurrence for the duration of the spell.
Base 10, +1 Touch, +2 Sun, +1 for Mentem req to restore the target's human mind.
Thats how I would do it.
btw, mean_liar, I also disagree with your interpretation. No Rego effect would be needed to restore the target's natural human mentality, merely a Me req in the reversion spell itself. The task here isn't to control the target's mind, merely to restore it to its essential human nature.
It could even be justifiably argued that no Me req was required at all since in this instance we are not transforming a natural animal to an unnatural human form, but simply correcting an unnatural transformation from human to beast. In that case it could be had for level 25. YMMV