does Mind Shield function like a meta-trait?

[Plane]

Initially I had thought of Mind Shield as sort of a limited kind of IQ (or form of Resistant) since it helps by giving a bonus to IQ rolls (and also Will rolls, a secondary derived from IQ) against resistable abilities with the "Telepathic" limitation.

IE kind of similar to "Mental Resistance: Psionics (Telepathy only)"

That would explain the leveled pricing system, which is linear based on what bonus you get.

It seems like there are other components I overlooked though, even in it's raw unmodified form.

1) "warns you of and defends against" seems like it's a kind of Detect against "mental attack" which might normally not make people aware if they made a mental resistance roll?

2) "resists attempts to locate your mind" sounds like it could introduce a resistance roll to situations which might normally had one: even a theoretical "level zero mind shied" giving a Quick Contest against your Will would be very valuable!

PP57 also mentions under "borrow skill" (a form of Modular Abilities) that "if he has Mind Shield, he may choose to resist"

This implies that Borrow Skill (ie modified Telepathic Learning) normally cannot be resisted at all by people without Mind Shield (they can't prevent their skills being copied).

if it was normally resisted by all, that would be an extra -10% limitation, as PU8 mentions.

It seems like, much like we have a "Magery 0" cost, prior to the 10/level you buy for 1+, that maybe there should be a "Mind Shield Zero" to reflect the two basic abilities (warning and resisting the unresistable) it imparts, prior to adding levels of Mind Shield to Will or IQ?

Powers also seems to have boosted mind shield a bit, since basic only talks about telepathic psi powers and "communication and empathy" spells, whereas:

P12 "diverting defense for any mental power"
P32 "resists all mental attacks, of any source, whether it’s a wild advantage or a chi, psi, or magical ability"
P62 "should let Mind Shield add to IQ, Will, and Perception for the purpose of resisting any paranormal influence"

If you wanted it to only stop a particular psi power (telepathy) or magic college (communication) per the basic set wording that would be like -75% x -75% = -56% probably?

This also brings up the question: could you have Mind Shield that gives the IQ (and thus will/per) bonus, but doesn't have advantages like "warned you" or "resist the unresistable" ?

I'm figuring possibly if you had "Uncontrollable" or "Unconscious Only" then since you're not the one using the Mind Shield (it's the alternate consciousness using it) then you wouldn't be aware it was being used (and thus you were under attack) ?

P70 mentions Mind Shield can help defend against Rapier Wit if RW is defined as a telepathy or chi power, which seems a bit inconsistent with P32's "of any source, whether it's a wild".

P153 also clarifies that while switching on a mind shield is temporarily sensable (to Detect Psi) as an "active use", the ongoing having the mind shield up is not. Probably counts as active to try to double it's level via "Power Block" though?

To get a "I can sense him while his sheild is raised" you'd probable need to give mind shield stuff like "maximum duration" so it would need to be re-raised a lot, I guess? Not sure what else would do it.

P159 mentions no simultaneous use penalty, the only exception I could see is maybe if you limited Mind Shield w/ "requires concentrate".

P169's overview doesn't seem to mesh up with being able to use it against Borrow Skill (Telepathic Learning) though: "Adds to any IQ, Will, or Perception roll made to resist mental-influence abilities"

Telepathic Learning doesn't seem like "influence" to me, because it's just about "what environment do I need to gain an advantage". Much like needing magic tomes around to learn a spell.

B173's mention of Force Field / Affects Others / Area Effect 3-enhancement combo also raises an interesting question: if people other than the user are attacked, are they the ones alerted about the attack, or is the owner of the Mind Shield advantage the one who is alerted?

[Donny Brook]

I don't know any of the answers, but that is a very useful survey of the rules.