Just a rules thought that occurred to me, wanted to resolve it before it comes up in game:

Okay; you're a mage; you cast a Stunbolt at a mook. He drops. You or a spirit take a number of complex actions equal to the Force of the spell (Force 4, for example's sake) to clean up your astral signature; otherwise, it'll last for 4 hours on the target.

Okay, now you're the same mage; you cast an Area Of Effect spell, say, Stunball on five targets. Do each of them need to be cleaned up individually? Or is it just one big signature?

And, to add a wrinkle to the scenario--which prompted this question to begin with--let's say your Stunball does not manage to drop all five targets. One or more manages to get away. Does the escapee carry a piece of the signature on them? Or can it be cleansed somehow, even without his presence?

Right now, I'm leaning towards the interpretation of "everything within the spell radius will carry the signature of said spell, and if something within that area leaves that area before the area is cleansed, then a separate action will be needed to clean up the signature. Otherwise, cleaning up the astral signature of a single, contiguous area requires only the standard number of complex actions." However, before I throw that up on my wiki's Official Rulings page, wanted to tap the DumpShock groupmind for some feedback first.

So, thoughts?

EDIT: Underlined bit that was added for clarity.

That's a bit of a tricky one. Give me overnight to read up a bit and ponder it and I'll get back to you.

The RAW suggests that everything affected will carry your signature this implies if you cast a fireball on a pile of trash with thousands of pieces you would spend days in erasing the signature which isnt really intended i think.

Our group interpretes the signatures as remainders of astral links which remains in the ambient mana SM p.55 Cleansing gives an example where a magician can erase signatures which seem to remain in the ambient mana.

In case of area spells you could assume that magicians/adepts are able to clean certain areas (think of scrubbing with your hand or blowing a cloud away) since movement isnt really an issue in astral space i think its okay to say that one spell leaves a sinature which can be ereased with one complex action per force.

But i agree the RAW spelling gives argument to a number of interpretations depending on how RAW you go.

Can all spirits do this? Can any? I expect one with the Magician quality (like a Free Spirit) can but do you have a quote to show that it can or others can?

Huh. I can't find it. I thought that they could... wonder where that idea came from...

Well, aside from picking nits--although thanks for correcting a mistake on my part--do you have an answer for my question?

I'm not suggesting it's an error: you may well be right. But before endorsing it myself in our game I'd like to see something that shows it's possible. I wouldn't consider it a nit-pick; if spirits cannot erase your signatures, then a Mystic Adept needs to buy the Astral Perception power to clean up. If spirits can do it, even a single skill point in summoning provides him with a concurrently active background astral garbage-collection thread plus all the normal utility of spirits. Of course, "for everything else, there's Manastatic".

My view on your question is just a case of practicality and logistics. If you're going to hold that "everything within the spell radius will carry the signature of said spell, and if something within that area leaves that area" you're going to have to deal with leaves being blown across the street and raindrops going down the drain. It'll be hard to chase them all down and cleanse them. Even if you restrict it, saying that magic is all about life and that the spell signature remains in one geographical location and isn't smeared by the movement on inanimate objects but does stick to any living organisms leaving the area, you're dealing with a planet saturated by life. Unless you've got Sanitise up, bacteria and fungal spores and yeasts are whizzing out of your area of spell signature constantly. But it would be handing mage players a gingerbread man to rule that metahumans who resist a manaball and flee have no residue of your signature.

Nope, I checked the book; it specifically says,

I.e. adepts need not apply. Also, spirits, and couldn't find that option under the spirit services listing.

As for the signature, I'd rule that it'd stick to any object or life form in the area that's big enough to be recognized as a distinct entity or shadow on the astral. Astral microscopes don't really exist, so... *shrug* You can't assense individual microbes. However, a "dumpster full of rotting food" is a distinct (very distinct) object which *can* be assensed for a signature.

I'm going to go against the grain here so far and say that the signature is left on the area of astral space the spell was cast in. If anything was there, or comes into or out of the area, it doesn't matter. To erase your signature, just concentrate on the area the spell was cast in.

If you go the other way, then metamagic that can clean it / cover it up is basically useless. There's air, microbes, leaves, dust, objects small and large, and people that could have been in the area when you cast the spell whose positions probably aren't going to remain static indefinitely and you'd have to chase them all down individually. So if you go this route, you might as well rule that such metamagic doesn't exist, as it doesn't have any practical use in the game.

For my table, at least, that's my call.

I too am of the mind that the mage needs to clean the astral space where he cast his spell, certainly in the case of an area effect spell.

You raise an interesting point though - if an individual was the target of a spell and that person was not dropped by the spell and managed to make good his or her escape, the mage might then have to hunt him/her down to erase the signature ...