I am a bit curious as I do not find any really good answer to tmy question...
If say that I enchant my sword to be able to glow and thus be a light source, will it only be resisted by MR if the enchantment is active.
Do I need to put extra levels into penetration for my glowing sword to be able to hit a monster with MR/Magi with Parma in order to bypass the MR?
Sword bright as the sun (CR IG 14)
Base: 4 (Create light equal to a cloudy day
Duration: Concentration (+5)
Special: Item hold Concentration (+5)
12 uses per day: (+4)
Do I need to add penetration in order to attack faeries, demons and magis with it?
You should be able to enchant a part of the sword, like the pommel stone, leaving the blade non-magical. If the pommel is what's magical/ends up doing the glowing, the blade shouldn't be stopped by MR. If the enchanted pommel makes the blade glow, then the blade is probably resisted a la pink dot when lit. I suppose you could try to be clever and enchant the air around the blade/sword to glow, but that would be higher level and/or more complex.
Another example would be a sword that is enchanted to parry the blows of incomming attacks from metal weapons. With the Sword's inherant bonus of +3, I guess I have to enchant the blade as that is what you parry with.
Would such a "Blade of Deflection" be useless against magical beings and those with Parma/MR and do I need to add penetration to the effect in hope of being able to attack and harm beings with MR
Strictly speaking I think the answer is yes, the blade will be stopped by MR if it is enchanted. And yes it will need penetration in each effect to strike.
I think a common house rule is that the item must have an active effect to be resisted by MR. If your group use that rule then it can have the powers invested and it can be used against MR as long as the powers are not active.
Never been able to find a line in RAW which states that a device which has been opened for enchantment is treated as an active magical effect, so I like the rule.
Carry a second weapon?
A lot of people say that the RAW dictate Penetration on inactive effects, but I don't buy it. I'll openly admit the rules aren't perfectly clear, but there's nothing to suggest that the ability to use an effect is resisted, only effects themselves are.
Regardless, though, RAW is often a meaningless sentiment anyway, so if there's a particular reason you want things to work one way in your saga, make it so... This isn't one of those issues with ramifications deep in every part of the setting.
I've always found that only enforcing Penetration of active as well as useful (e.g. non-cosmetic and non-trivial) effects seems most reasonable to me.
Compare with the situation of being attacked by a magical beast, say a bear of Might 10. Being mauled by the bear's claws is not resisted. But if the bear activated some kind of effect to make his claws nasty, like a PeTe(An) effect to rend the target's armour, then you need to look at Penetration.
Back to the magical sword. How is it magical? Whacking someone with it, using it just as a sword does not IMHO need to Penetrate. Activating the Edge of Razor or Blade of Virulent Flame does.
But if the sword gives off a glow, or maintains a Doublet of Impenetrable Silk on you - effects which in no way affects the poor enemy you hack away at - why the deuce would you require it to Penetrate? That's too Pink Dot'y to me, and I'd like to not bother with that.
Same as above.
I differentiate magical item from magical effect, as well as direct, active effect vs indirect, passive effect.
Thus a "Sting-like sword" (Bilbo's sword in LotR), which glows when gobelins are nearby, won't have to bypass MR to inflict normal damage versus the opponents it was designed to fight against.
As a personal house rule, the magical bear mauling an opponent with magically poisonous claws (for example), would still do normal damage vs somebody with a MR able to resist the poisonous effect instead of completely stopping the claw.
Check out page 97 of the core book, middle column under Preparation for Enchantment and the example of the staff and ruby. You can enchant the effect into the pommel stone and draw on the shape (but not the material) bonuses of the sword for the enchantment. If you design the deflecting effect with a Momentary Duration, it should only be blocked by MR when it's busy deflecting an attack and not really be an issue.
As Ironboundtome pointed out above, by strict RAW, yes, a glowing sword needs to penetrate.
The alternative is Magic Resistance (ie. Parma) being intelligent - able to seperate dangerous from non-dangerous effects, something I'd personally prefer to avoid.
It is a very common house rule though, possibly even more so that the fix for penetration for charged items.
I've found intelligent Parma Magica is harder to consistently adjudicate, where as any active effect is very simple (likewise the problems with wards).
The sword hilt can still glow, or have a gemstone on the weapon glow.
The reason I ask is that a player of mine wants to make a sword that has a rego terram effect which gives a bonus to defend while wielding the sword.
This is the effect that he was thinking about in a lesser enchanted device:
Rego Terram: Level 19
Base 3: Move metal in in a very unnatural way
Target: Touch +1
Duration: Diameter +1
Target: Individual +0
Affects Metal: +2
6 uses per day: +4
The thought is that the blade would give +4 to +6 in defence value.
Would a sword like this need Penetration as the effect is only affecting the wielder
This would require the wielder's blade touching the attacker's blade to work at Touch range. Diameter duration is probably less than desirable in this context, because the effect continues to act on the blade. Unless that's the intent, that for two minutes after the blades touch, the opponent's blade is unwieldy giving the defense bonus?
Magi of Hermes has Wizard's Parry which allows a full outright parry of the incoming blade as a fast cast defense. While I don't think the spell as presented (has R:Touch) works as intentded, changing it to voice only adds a magnitude. An effect that does that is as follows:
Wizard's Parry (item effect) 25
The effect allows the wielder to parry any single incoming attack that he is aware of.
Base 2: Move dirt in a slightly unnatural way
R:Voice, D:Momentary, T:Ind, +2 Metal
+10 Frequency Unlimited, +5 Fast Trigger
I'm not a fan of the spell Wizard's Parry, but it is canon. I would probably require a Base 3, +2 metal to outright do a full parry (your presentation), and use Base 2 (Wizard's Parry) to provide the defensive bonus. After all, you're just moving the blade a little bit so that the defender actually misses.
I don't see how it affects the wielder; it affects the sword, moving it. I see Rego spells in general as controlling specific movements (or changes), whereas this one requires case-specific control over the blade's motion, something that I would associate with maintaining control (Concentration) over the spell. So I would change the Duration to Concentration; I'd lower the Range to Personal, as it affects the item itself; and I'd peg the bonus as +3. The problem with using this Power will then be that it requires Concentration checks. Alternatively, I'd allow an Intellego Terram effect at range (Voice for "whistling" sword?) to detect incoming attacks, with a connected Rego Terram effect to deflect them to add up to a +6 bonus; but then, this would not be lesser enchanted device.
As for the MR, however - I reckon only effects active on the item are resisted. So if the item affects the wielder, as you say, then the effect needs to penetrate his MR to affect him. If the item affects the sword, then while this affect is on the effect's Penetration must penetrate through any opponent's MR for the sword to strike him.
If you adopt a house rule on MR, both of these may be waived, but as noted above this is problematic. A variant for your consideration is "MR strips magic" - the sword, if it hits, uses its basic stats plus any stat-changes or extra damage due to effects the do penetrate, but not of those that don't penetrate.