For one extra point of drain I can create the ultimate invisibility spell…

Just add “Multi Sense� instead of “Single Sense�.

Now we have a Realistic Multi-Sense spell that affect and fool ALL senses.

Now, remember that Astral Perception IS a sense.

Now, how would this pan out?

Would the perceiver have to pierce the illusion in order to even see the spell on the astral? We can even make it more extreme and make a pixie mage with magic rating 6.

Pixie gives a -6D6 to all perception tests (including astral perception)
Then we add a “Vanish� spell like the one above.

Now, just to see the pixie is at a -6D6 regardless of plane, and then we make it even harder with the spell…

A few oddities that comes up with this…

Cameras, drones and sensors
Are these considered as doing “Perception Tests� in order to see the pixie? Im inclined to say yes.

Astral Perception and spells
How obvious are spells on the astral
How obvious are spells on the astral when concealed by other powers
Would there be a threshold to even see a spell that actively “jams� your astral perception?
What would apply first? Concealment power, Spell Effect, Active Spell being Obvious?

/e Head explodes..................

Several obstacles:

• Spells are limited to one plane. A spell that affects sensors can´t affect a spirit on the astral plane. You can´t get all potential observers with one spell.
• I would, for balance reasons, not permit "multi-sensoric" illusions to work against astral perception.
• If you see that differently: An invisibility spell turns the target of the spell invisible, not itself - it is obvious on the astral plane. Including those observers that failed at spell resistance and can´t see the caster.
• Physical devices don´t get resistance tests, you beat the threshold and that´s it.

(See the main book on spellcasting and illusion spells.)

Good point, I should have thought of that.

Well, that matter IS moot since as you said, it wouldn't work on that plane. The question is what would happen if you create a single sense "Astral" invisibility spell...You would in that case be able to be invisible against astral critters, regardless if the spell is visible since you have fooled them with a "see me not" spell. You would on the other hand be fully visible if a spirit materialized...

In the case of Pixie/spirit power of concealment on the other hand their Dicepool would suffer for sensor tests and detection dice rolls.

Also of note: Just because you have a spell or critter power making you invisible doesn't mean the spell/critter power is itself invisible on the astral. At best it'd be a magical disguise carrying an astral signature that can be masked or fluxed but not made invisible itself.

Have to agree with Wasabi there Jopp (Wotcha there btw - long time Term). A magical effect is evident on the astral unless its somehow masked or concealed by astral effects like background count fluxuations. Wouldn't happen to have a Horror or two lurking nearby perhaps, hmmm?

Illusions never work on the astral (or more specifically, they work, but they're obviously illusions).

A better spell is some sort of a manipulation spell which makes the target refuse to acknowledge you exist. The target sees you, but doesn't care. Then it works on any plane.

Slightly off topic but still to do with invissibility and senses. I know Physical Mask spell will fool devices as it is a Physical spell, would that include fooling MAD detectors?

No

And of course, it works against Spirits, external Sensors - heck, even people not affected by the spell warning those affected by it.

Magic isn't that obvious. While a character wouldn't get the benefit of an invisibility spell when sneaking past astral observers, he wouldn't be any more obvious either. I wonder about the concealment power though. It says that it penalizes perception tests, but astral perception uses Assensing, not the Perception skill. If that's true then it's not really possible to hide yourself from astral sight, it would just be a straight up infiltration test. If anyone has any ideas about how to hide on the astral plane, I'd like to hear it.

My group ran into this today, actually. The guy reading the book indicated that the Concealment power does effect the astral. I mentioned this thread, we went with that ruling, and moved on (a force 6 spirit Concealing the group + the astrally hazed guy messing with magic in general).

Could you give a quote, please?

Actually, Astral perception is just like any perception test in order to find something. WHEN the magician has found something THEN they can make an assensing test to find out more about it. See page 182 SR3 about astral perception:



End Result: Standard perception test using Astral Perception

When the magician has managed to see soemthing hidden on the astral (concealment) then they may make an Assensing test.

Question: Are spirit powers limited by plane? In that case then concealment should only work on either astral or physical, not both at the same time.

I do not agree with your deductions. A Perception Test is a test involving the skill Perception unless specifically extended to tests using other skills. Also there is the capital P, Perception is the skill and perception is any way of gaining information about your surroundings using senses or sensors. The Concealment Power speaks of Perception Test. So it does not work against astral perception just as it does not give a penalty for targeting mundanely or magically.

By your logic a spirit should also be able to conceal (living) personas, and that sounds just wrong.

I believe that we actually have the explanation within the power description.

Concealment is a physical power and therefore it does not affect astral perception. I believe this is also needed in order to affect machines.

So, no, the Concealment power does not function against astral perception or assension test.

So, if you want to hide on the astral you must make a stealth test VS assensing test.

Yup and using Logic instead of Agility.

As a side note, what happens if someone is searching for a sneaking mundane character using astral perception, how can he defend against being found?

Yeah, that's my question too. I'm rather certain it's possible to use Infiltration to get past Astral security, but I couldn't see how you would do it unless you were astrally perceiving or had forknowledge of the astral security. Does anyone know of any usable skill, spell, or ability that can help hide on the astral plane, besides something like a background count?

Nope.

The power of Fading - which I don't think exists in 4th Edition - would do it. To my knowledge only Leprechauns had it, though.

Using cover on the physical plane should conceal the sneaker on the astral as well. However astral creatures can move a lot faster than physical ones, so cover would be less effective as an observer could easily look on both sides of the cover before the sneaker could move to the other side.

Concealement can affect the astral plane. A spirit using the Search power gets a dice pool penalty to find a target that's being affected by concealment. Since this is a watcher spirit's only power and a watcher spirit can only exist on the astral plane, this means that concealment has to be able to affect targets on the astral as well as physical plane. I know this is a somewhat obscure reference, but it does throw a little doubt on the perfect Astral Perception security scheme.