Is a suit of armor considered an individual for spell targeting purposes?
Is a suit of armor considered an individual for enchanting purposes?
If not, can it be enchanted as a group, or does each part of the armor have to be enchanted separately?
Thanks in advance
I would consider a suit of armor a sngle individual for these purposes.
Depends on exactly what the effect is, and what you mean by "a suit" (and whether you believe "a suit" even exists as such!)
If you mean a suit of chainmail, hood to waist and wrist to wrist, then I'd strongly argue that each link is not an "individual" for most purposes. But the torso and pants might be, as would the helmet over the (attached) chain hood.
If you mean a metal breastplate, metal elbows, knees, and helmet - then I really don't see any unifying aspect other than the person wearing them all. And remember - there are no "metal suits" at this point in history, nothing like this:
That's "Gothic" era, at least 200 years (or more!) down the line.
Typical armour in the 1200's was a piecemeal affair, a combination of fabric (He), leather (An) and metal (Te):
...or...
That said, to be playable, at times "armour" has to be treated as a single thing, esp when "enchanting". (Or, a large enough piece to be representative of the whole, depending on what's happening.) A mail shirt could be made "more resistant" and work fine for overall protection, but a single bracer (fore-arm guard) or helmet could not - that would need a Ward effect, or something more creative/magical in end effect.
Remeber - AM magic, as written, doesn't do "stuff", it has specific effects that are then applied to the environment in "realistic" ways. You can't necessarily take steel and make it "+50 soak", because steel can only get so hard, and after that the wearer just isn't that much better protected. (Or, I wouldn't allow it, anyway - ysmv.)
I agree, overall. If a 'suit' is made up of bits all attached together, then I'd allow it all to be enchanted as a single item. But I'd also allow (for just an extra magnitude) one piece to be enchanted so that the 'suit' it is then attached to is all affected by an appropriate enchantment. eg Enchant a breastplate so that it and any attached bits have increased soak. That way you can replace worn parts without needing to re-enchant anything. There is an example, possibly in the old rulebooks (my memory tends to mix these things up), where two options are given: one where an entire staff is enchanted; and one where just a ruby set into it is enchanted, with the same overall outcome (except that in the 2nd case, whilst damage to the staff stops the effect from working, once a new staff has the ruby in, it works again without any lab time needed).
If I were casting a spell at an enemy and I wanted to affect his armour only, I'd expect to be able to do so without needing a 'group' target. I might need 'part' to avoid the person wearing it, depending on the spell and the SG. Enchanting should be similar to spell casting - it's all Hermetic.
Steel itself might top out for protection, but if you are pushing that limit your PCs should be looking for mythical/magical materials - eg mithril? (Or aluminium/titanium alloy, as I like to think of it...)
Gilarius
I've had this discussion previously, and don't care to repeat the entire experience. If anyone disagrees, that's fine - ysmv and all that.
But my view is this...
Armor protects. If you make armour "harder/tougher", it protects better and better - but only up to the point where no mundane weapon can penetrate that armour. And while there is some chance that a "lucky hit" can penetrate "double tough" steel, at some point pretty quickly it's just not physically going to happen, regardless of the critical rolled. 1000 grogs with mundane daggers will just simply never penetrate a two-finger-thick plate of steel (or it's equivalent) in a single swing, not even in 1000 years, regardless of how many "1's" they roll in a row. The dagger just ain't gonna go there. At some point, and pretty quickly, "toughness" has exceeded all mundane threats to penetrate. Agreed?
Thought so (Hope so!). Now...
A "suit" of armour is not, in fact, a hermitically sealed second skin. There are joints, there are gaps, there is actual living skin showing - the armour itself has some "holes" in it, by necessity of design.
Long before "tougher material" has topped out, attacks are still getting in via bypassing the material itself, through these gaps. So the difference between "mithril armour" and "adamantine armour" and "diamond-adamantine armour" and "triple strength diamond-adamantine armour" is... nothing. The attacks are not going through, they're going past. They're finding the seams, the joints, the gaps in any armour, no matter how tough.
So, how to make armour "better" beyond just Muto'ing it toward infinity? Well, short of creating a diving suit of triple-strength-diamond-adamantiuml with a Muto-clear face-helmet and CrAu breathing gear - get creative! Use Rego to make it move easier, Intellego to help the wearer "hear/know" where the attacks are coming from - things that help Defense rather than Soak. Re/MuCo to make the wearer stronger/faster. Creativity, rather than just dull "BIGGER NUMBRZ". That's how.
imo. ysmv.
Like it, love it, agree with it all - except that, whilst mundane weapons do exactly what you said, what about the humungous earth elemental that just stood on you? Having really strong armour that can withstand entire mountains being dropped on you can be useful, occasionally. 
(Yes, I had that happen - the two PCs under it just teleported out unharmed, having soaked over 300 damage. It was a very small mountain, though.)
Having creative spells do all the other (and more) effects as well is far better than just super-duper armour. My 4th ed over-the-top rego specialist had a list of moon duration defensive spells that was longer than many character sheets (one line per spell, covered 3 sides of printed A4. MuCo soak boosts, we ruled, limited sensitivity, touch, etc. And boosted strength needed boosted dex and boosted perception to avoid us accidentally putting our hands/arms through any grogs/walls/etc while we waved our arms around spell-casting...), but that had to end with all the warping in 5th ed. Now, they are much better as enchantments built into clothes and armour (and less vulnerable to Mu or Pe Vi attacks).
So many ways to die, so many ways to try to prevent them! Paranoia can be fun! And it can be fun inventing magical power armour - remember that you want the armour to gain all the bonuses in 5th ed (to avoid warping the wearer) so the armour gets the strength and speed boosting spells, not the wearer.
Gilarius
Oh, just a small mountain? Well that´s ok then... :mrgreen:
Except its no longer "steel" you´re playing with, it´s "magicked steel". I dont mind allowing it to be improved "endlessly", but beyond a point, the increase from each magnitude the effect is raised will be less than the preceding one. Down to the point where you need more than one magnitude just to get +1 to soak.
Anyway, the important part being that "steel cant be like that" just isnt relevant.
Aside from that i agree.