A) One of my PCs asked whether a mage could cast a spell against you (we'll go with Manabolt here since it only affects the living) if your body was encased in opaque materials like when wearing the Full Body Armor.
He brought up the point that you couldnt see through walls while you were astrally perceiving (one of my PCs wanted to do that but we figured the RAW said no) so your aura wouldn't bleed through that armor either, would it? Auras don't 'bleed' through things unless you're forcing your way through, right?

B) Also, would coating your armor with mirror-like rflective material reflect spells back at a mage or other reflected objects?

C) Would readying an action to raise a mirror at the same time as a mage is casting his Manabolt spell at you reflect it away, possibly at the mage if you know where you're pointing the mirror?

Note: I haven't let any of this affect my game yet. No one has gotten away with any of this yet so please no "don't be a pussy GM" or "Just fudge rolls and drop cows on them if they're trying to be clever and inventive" comments. Thank you any help you may give

a) They can still target you. Your aura encompases your body and a small field around you. I can't point to an SR4 rule because I have no books handy, but this has been the way it's worked in all editions. Clothing or armor by itself cannot make you immune to magic.

b) No. Targetted spells are targetted on the person, not on "whatever is in front of my eyes." You could possibly cause the caster to catch unintended targets in the area if their reflection is in your mirror, but for something with as many angles as armor it would be pretty rare IMO.

c) Again no, because targetted spells target the person. The comments about targets for area spells also apply here, but a flat mirror will be much easier to use for the purpose.

Keep in mind that by most fluff magic works metaphorically, not according to mundane things like physics. While the armor isn't technically part of the person by physical standards, metaphorically it is part of the person because dress makes up as much, or more, of a person's apperance or image as does hairstyle or eye color. The only way a combat spell would ever deflect or reflect off a mirror is if it were a light based elemental effect, say for example your mage had written himself a "Laser Beam" spell for some incomprehensible reason.

A) Yes. A persons aura is supposed to surround the body extending to several cm. Kind of how an electromagnetic field surrounds planets and some electromagnetic devices. The stronger the persons health and essence the brighter and larger the field is supposed to be. The clothing can not push aside the field because it is fully contained within it, where a wall can.

B) I supposed you could get some kind of enchanted counterspelling focus clothing, or when Street Magic come out something that acted like the Reflective Metamagic in 3rd. Regular mirrored clothing would not affect spell casting because the mage can still see guy in mirror suit looking for the disco. However, you might give the mage some flash modifiers depending where the sun, or other bright lights are. Mirror outfit and flash grenade.

C) NO. It would have to be a pritty good sized mirror to block LOS.

I look at it from a D&D point of view (just follow me here). If a character has a tower shield, they can take full cover behind it, making it so that all attacks hit only the shield. However, spells can still target the character normally because the shield is "part" of them.

No, no. I definetly follow the D&D example (and the rest for that matter.)
There's nothing wrong with D&D, except maybe the Book of Vile Darkness. Pregant four armed demons is messed up

ah, magic vs "physics"...

magic targeting have allways been a bit wierd in SR, and SR4 dont help it (suddenly you must see people even when you use a elemental area attack?).

heh, there is even a canon comment about looking thru a keyhole to focus a area spell onto a single target (the book in question, sr2 grimoire, more or less suggests hitting the player over the head with a book).

Then stop being such a hermit

Related question: The books do specify that visual modifiers apply to casting magic, including partial cover (good cover = 50% hidden = -4). How much of a person's aura must be exposed in order to target someone? If someone just sticks a finger around the corner can they be targeted? What if they're leaning against the car's tinted windows - some of their aura would supposedly be poking through the glass?

I've always played it as "you are what you are plus what you wear." Leaning against a window won't make you targettable if that window is opague. That's just me though, and I don't have any rules references for it.

Bearing in mind I'm probably completely unqualified to say this...

If one were so inclined as to tote along a full tower shield with the express intent of denying mages LoS to their body, I would allow it. Actually, that's not a bad idea - a couple of guys could take cover behind a troll-sized tower shield.

Plus of course, it's going to have a barrier rating of like, 12 or so, meaning you can advance under fire. (Carefully, and being wary of grenades.)

And weigh a shit-load I'm not convinced I'd deny mages LOS, maybe just give the target some cover modifiers. Although it'd be easiest for the runners to just run in the oher direction. Shield guys aren't going to be able to keep up.

Speaking of the Book of Vile Darkness, I have a friend who can't read that without giggling (at length) about the Nipple Clamps of Exquisite Pain. That is the primary reason to discard the Book of Vile Darkness.

Or the zombie spewing cauldron.

Zombie spewing cauldrons are fun! If you're looking to play a zombie filled town where the goal is to escape before dying zombie spewing cauldrons are the easiest way to set it up.

You're immune to all effects taht work off pain as they convert all pain to pleasure. It doesn't change the damage you take, but may change how you react to it.

Plus they have little tassles you can twirl 'round for your girlfriend

at least the BoVD isn't as crappy as the BoED.

i mean, i could actually imagine at least some of the stuff in BoVD being used legitimately. but all that exalted stuff? honestly, if you're playing exalted characters, you're not playing D&D...

Vow of Poverty my ass. I'll take my magical items thank you very much

no kidding. you get to keep the magic items if you accidentally stub your toe and swear, or get mad at the orcs who are trying to kill you, or if you step on an ant. i wouldn't be too sure about that with anything that requires [exalted]...

do they have the tassles?

Cybertassles baby! Oh yeah!