Salvete, sodales!
I'm wondering whether it's possible to make an illusionary quality appear differently to different people? Think of an empty canvas, where anyone could see an attractive individual or a mirror that makes anybody else (save for the one looking) look hideous. Would a mage need Imaginém or Mentem spells?
Also, I'm wondering, whether it's possible to distort the perception of time with any of those Arts.
Imaginem affects species, so I don't see how a spell could tailor the species emitted according to the persons perceiving it.
It would better be suited for a Mentem spell that would convince the target that what they are seeing is something different, according to their imagination/belief/hope. If the person believe that he is the most beautiful, the spell will makes him believe that each time he sees himself, he is the most beautiful. The spell does not change the perception, but how the target appreciate or understand said perception.
And I believe, a PeMe could alter the time perception. There are no guidelines for such effect, so some guesstimation needs to be done:
PeMe 10: reduces all of a person's mental capabilities seems a good base to reduce the speed a person think, understand and react. Probably making him/her able to only act every other turn.
MuMe or ReMe could perform similar feat, but again there are no guidelines for that. I would be tempted to rule that Perdo is the most suitable form for that, so achieving similar effect with another technique (Rego or Muto) should be one magnitude higher - we are entering the domain of YMMV.
You can perhaps achieve this effect by lighting the illusion with magical light, which is blocked by magic resistance, but the limitation is that the the illusion is only selective across the penetration of the light
I like this idea quite a lot! Though, wouldn't you need separate penetration rolls?
The Societates section on Jerbiton has lots about Imaginem, including creating images that are only visible in certain directions. Tie that up to some kind of InCo spell to detect people and their movements, and you probably can have illusions that are different for everyone. But ooh, that sounds quite high level to me.
But you could also use Mentem to convince people what they are seeing, regardless of the species hitting their eyes. That might be easier, as people will fill in the details themselves. But that also makes it more likely to be found out by careful investigators.
@Multus roll penetration once, compare to various targets as necessary
@Tomaso perhaps could be done using a combination of spells(or item effects) using muim
Multus said in another thread he/she was looking to play Ars Magicka 4th, so I suspect that references to 5th edition doesn't help.
Ah, that's fair, I assume the optics stuff is the same though?
Ah, sorry, didn't know that, and I have no familiarity with 4th edition.
I'm flattered to be looked after, I do appreciate your hospitality!
Though, this question is a tad abstract, so I decided not to specify the edition, since it may discourage some answers. I would probably broaden my list of sourcebooks in the future (if it becomes possible).
For example, it didn't occur to me, that Jerbiton would specialise in illusions, but now it makes a lot of sense and my imagination's gears've begun grinding!
Yes, in v5 at least, Jerbiton are really into illusions: they are subtle, non-lethal, and artistic, playing to three of their favourite things.
I think you could use MuIm to change people's reflections in a mirror, maybe making everyone look taller or black-and-white. For the blank canvas, I think you'd need Cr as well: I think stretching MuIm to "blank canvas now looks like a painting" is too much.
You could also use MuIm to make those illusions different at different times, but if you want people to see different things at the same time, that should make the spell harder because it is doing something fiddly.
I also think if you want the images to reflect something about the individual (such as showing them a picture that they find attractive) you need some kind of Intellego requisite so the spell can "know" what it needs to do. So that might be InMe for "what does this person think is beautiful?" or InCo for "which is the reflection of this person, so I can make their image unchanged while everyone else is ugly".