[Mollari]

Question: What do people resist illusion spells (mask, invisibility) with?

By this I don't mean the individual's or object's resistance test to stop the spell taking hold, but rather the penetrating test.

eg. mage spots the street sam approaching. He pops a spell of improved invisibility and disappears off natural and technological sight. The street sam does what test to penetrate the invisibility? Perception? Intuition+Logic?

Thanks guys.

[firebug]

If you look in the core rulebook, in the Magic chapter, in the list of spells at the start of the Illusion section (pg 290), you'll find out.  I'll post it here for you.

Mana Illusions: Mana-based Illusion spells affect the mind and are ineffective against technological viewing systems like cameras. Mana illusions are resisted by Logic + Willpower. Some mana illusions affect the target’s senses directly; others affect the senses of anyone perceiving the subject of the spell (though you’re never affected by your own illusion spell). Though mana-based illusions can be created on the astral plane, their magical auras give them away as illusions to anyone who makes a successful Assensing Test—illusions can’t fool Assensing and cannot be used to disguise or create auras.

Physical Illusions: Physical illusion spells create actual images or alter physical properties, such as light or sound. Physical illusions can be used on both living and technological systems. They are resisted by Intuition + Logic; non-living devices resist with their Object Resistance. The magician must generate more hits than the observer for the illusion to be considered real. If the spell is not completely resisted, the target is fully affected by the illusion.

Then you look at the spell being cast; usually for Illusion spells there's a Mana version (Mask, Invisibility, Phantasm) and a Physical version (Physical Mask, Improved Invisibility, Trid Phantasm).  The threshold the resistance rolls have to reach is the hits scored by the spellcaster on their initial Spellcasting + Magic [Force] roll.

Keep in mind, Illusion spells cast right in front of people can be self-defeating--  As per the rules on page 280-281, whenever a spell is cast, it produces some kind of noticeable effect.  People can roll Perception + Intuition (with a threshold of (Force) - Spellcasting of the caster) to detect it being cast.  This is more than just visual, it includes auditory and maybe even other senses.  So a F6 Invisibility spell cast by someone with 6 Spellcasting has a threshold of 1 to notice it being cast; there's some flashy effects and probably a sound or two.  This doesn't let people know where the invisible mage is; it doesn't even let them know that invisibility was the outcome.  But it does let people know you were there at least and that some mojo went down.

[Stainless Steel Devil Rat]

Pg 290 answers this.

Mana Illusions: resisted by Logic + Willpower
Physical Illusions: resisted by Logic + Intuition (or Object Resistance)

[Mollari]

Thanks guys. See I took that to mean resisting spells cast against you. So if an enemy mage wanted to cast silence, invisibility etc. on you, then the unwilling recipient of the spell gets to roll willpower+logic or intuition+logic to resist.

I wasn't sure if it also included people piercing the spell of a mage casting on themselves.

[firebug]

Silence is an AoE, so it isn't really on a specific target (thus, everyone who encounters it rolls against it).  Invisibility though, you can't actually stop someone from casting it on you.  It just, doesn't have any drawbacks to the person it's cast on.  So, they wouldn't roll to resist anything.  In a way it doesn't really "effect" them.  It effects everyone else who needs to resist it to see them.

[Stainless Steel Devil Rat]

Silence is an AoE, so it isn't really on a specific target (thus, everyone who encounters it rolls against it).  Invisibility though, you can't actually stop someone from casting it on you.  It just, doesn't have any drawbacks to the person it's cast on.  So, they wouldn't roll to resist anything.  In a way it doesn't really "effect" them.  It effects everyone else who needs to resist it to see them.

It's arguable that it's within the spirit of the rules that you get a roll to resist any spell that's targeting you when you're not consenting to it being cast on you.  Even if it's generally considered a harmless spell that doesn't get a resistance check explicitly called out in the very bare-bones technical language.

[Mollari]

Ok, so let's roll with this.

Mage casts physical mask to infiltrate a building. Guard at the door rolls logic+intuition to pierce the spell. If he does he suspects what he sees isn't real, if he doesn't then he believes.

Thanks guys for clarifying.

[Stainless Steel Devil Rat]

Ok, so let's roll with this.

Mage casts physical mask to infiltrate a building. Guard at the door rolls logic+intuition to pierce the spell. If he does he suspects what he sees isn't real, if he doesn't then he believes.

Thanks guys for clarifying.

Assuming the Guard successfully resists: I'm not sure if he just fails to see the illusion whatsoever, or if he sees "obviously phony" magic at work.  Could potentially make a difference.

[firebug]

I also believe it's supposed to be "obviously phony".  If someone succeeds to resist Trid Phantasm, I'm pretty sure they don't just not see the effect.  It just doesn't convince them at all.  After all, you can record footage of a physical illusion.  I know, I know, "it's magic!" but SR isn't the kind of setting where two people could look at the same entirely mundane photograph of a mage using Physical Mask and actually see two different photos.  Magic doesn't work like that.

However, I don't know of any official stance on this.

[ShadowcatX]

The people viewing a photograph don't get a roll, the camera gets a roll and that determines what the people who look at the photo see.

[firebug]

True, though still, I don't believe the camera/drone resisting the spell means the illusion that explicitly is creating actual light and sound doesn't show up on the footage.

[Stainless Steel Devil Rat]

What about Improved Invisibility then?  If the observer resists the spell, the target is not invisible to that observer.  It categorically cannot be actually invisible, even from a physical spell that's actually manipulating light.

Wouldn't a camera that resists an Imp Invis spell just fail to show any magical effect going on at all?

[firebug]

That is a good point.  It could show a faded version of them, partly see-through, etc.  My logic is just "success should not remove information" in this scenario.  I really wish the books hadn't basically gone out of their way to avoid explaining this point.  Like, thanks, I really needed two sentences saying the same thing ("if you fail to resist you're affected by the illusion") when it's already implicitly obvious.  x.x  Christ.

[brombur]

Is there any thing in the rules about mages constantly recasting Invisibility to get a large number of hits to ensure they won't be seen?

Also

I see Ultrasound devices have a rating from 1-3 and that the effect defeats visual invisibility. So the rating isn't relevant to see the invisible target just for, I imagine perception tests or hacking attempts use this rating. Otherwise the user can just the hidden mage.

If the mage used Invisibility to mask sound then I think the silent area could be seen and then a perception test might be needed and would impose some sort of cover or blind fire mod to the shooter

[firebug]

Is there any thing in the rules about mages constantly recasting Invisibility to get a large number of hits to ensure they won't be seen?

No, a mage is free to re-cast a spell as many times as they want.  They just have to deal with the normal risks; every spell cast is a chance at drain, and if they're hiding while doing it, people will have a chance to perceive the spell being cast every time.

I see Ultrasound devices have a rating from 1-3 and that the effect defeats visual invisibility. So the rating isn't relevant to see the invisible target just for, I imagine perception tests or hacking attempts use this rating. Otherwise the user can just the hidden mage.

If the mage used Invisibility to mask sound then I think the silent area could be seen and then a perception test might be needed and would impose some sort of cover or blind fire mod to the shooter

I got a little lost trying to understand what you were saying, so excuse me if I'm a little overly-general here.

Someone could use an Ultrasound device to detect where an invisible magician is, but they'd still probably get the blind fire penalty, you just could actually try and shoot at them.  A -6 is a world of difference from "I don't even know where to begin firing".

If a mage used the Silence spell to make sound in an area (Invisibility doesn't do that) while also sustaining Invisibility, it's possible someone could be alerted if the silenced area suddenly encapsulated them and they were unable to hear anything or make any noise, but that would do little to tell them where the magician using the effect is.  It'd also be more logical for the magician to just use Hush on themselves instead.