Here's the question:

Person A is wearing an anchoring focus which has a bullet barrier triggered by a detect bullet spell.
If a mage is in astral space next to person A and person gets sniped. Can the mage attack and destroy the detect bullet effect as it attempts to trigger? Must he attack the entire focus? Can he target the spells as they are cast? Can he stop the barrier from coming up by destroying the detect?

Thoughts?

Sunday.

The detect bullet effect is constantly going, the barrier is only 'intermittent'. He might be able to engage the spell in astral combat (did they keed that in 3rd edition) but it will take a while (a complex axtion to the combat, at least) So 'interupting' the bullets flight time to fight the speel seems unlikely. Attacking the focus would also be a complex action, so again doing it during the bullet's flight (unless we are shooting form far away) seems unlikely.

You can't attack spells anymore in 3rd Edition.
You have to attack the focus, and given the process to do that, I think that doing that at the very moment the bullet is shot is too late.

He wouldn't really have time to destroy the focus in between the bullet firing and the barrier being erected.

However, a mage could provide the bullet with spell defense. That would allow it to resist the Detect Bullet spell and perhaps avoid triggering the barrier. He'd have to be physically present for that, though.

I wouldn't allow that because the mage cannot see the bullet.

I don't think you need to have LOS to provide spell defense. The only restrictions put spell defense is that the target must be on the same plane and within magic attribute*100 meters.

While we haven't seen a LOS requirement for Spell Defense in the book, our team plays as if it was required. Probably many groups play that way. We require it during the Free Action to allocate Spell Defense, and when the Spell is cast, but we don't require that the magician be able to see the Caster of the spell.

If you want to be particular, allocating Spell Defense is a Free Action, and a magician who can take a Free Action does so at the end of the phase when someone else is shooting.

Magicians may attempt to Dispell a spell maintained by a Sustaining Focus or an Anchoring Focus, but don't give Spell Defense to bullets in my game!

I should've been much more specific. I figured that the mage in question had looked at the bullet and assigned spell defense prior to it being fired. I also require LOS to initiate (but not maintain) spell defense in my games.

I don't think he could assign spell defense while the bullet is in flight, only with prior coordination with the sniper.

Good answers, much to digest, thanks guys.

Course the biggest eye opener is the "You can't attack spells in 3rd ed" which reminds me I really need to reread this stuff... take too much for granted as make assumptions that turn out to be outdated by rules updates.

So if you can't attack spells... make A has armor up, Mage B is astral. Mage B cannot attack and bring down the armor spell? His only choice is unweaving or whatever it's called?

Sunday

In 3rd Edition we use Dispelling to make the spell go away, not attacking the spell. However you must be on the same plane (astral or physical) as the spell to use Dispelling. SR3 p. 184.

If the spell is sustained by a focus, you can attack the focus astrally. SR3 p. 176 "Astral Objects". See paragraph 2 for astral combat (Charisma in opposed test with Force), and the last paragraph for throwing a mana spell at the focus on either the physical or astral planes.