What are the best magical systems in GURPS?

[Plane]

Anyone know why Magic Resistance does such an extreme 'no spells at all' even at level 1, instead of just acting like a double-edged sword and penalizing?

Kind of like how Mind Shield works if you take the PP15 "Feedback" limitaiton. A soft cap.

Originally Posted by kirbwarrior

I think Immunity to Magic is strictly better

Resistant gives you bonuses to Resistance Rolls when you get them, while Immunity lets you automatically pass those rolls when you get them.

You don't get Resistance Rolls at all against spells not listed as "Resistable", and even with those, you don't get Resistance Rolls if they critically succeed.

That's where Magic Resistance seriously pulls ahead of Resitant to Magic / Immunity to Magic, because it can target the basic skill roll and cause failure, regardless of whether the outcome is resistible.

By dropping skill below 16 or 15 you remove 6/5 as crit success results, so you only need to worry about the rarer 4/3 results.

Also useful in creating more crit fails: especially in wild mana.

I don't think lowering effective skill past 3 prevents attempts (since you may not know the penalties a applying to you when attempting it) but if it doesn't, it probably shouldn't be a crit success anymore, or even a success at all (like firing a skill 20 gun with -100 range modifiers)

Originally Posted by kirbwarrior

it's not Static which does have downsides

Static (Magic) is probably cheaper than the amount of Magic Resistance it'd take to adequatly lower the skill 99 of some ubermage. Mana Damper can sometimes compete but I don't think Static (Magic) can be counteracted by Mana Enhancer, that's in it's favor.

Originally Posted by kirbwarrior

it was pointed out to me that being immune to drugs shouldn't make you "immune" to 1-up mushrooms

Why not, if they're drugs with a resistance roll? If there's no resistance roll to 1-up mushrooms it would ignore resistant/immune though.

To make resistant optional (temporarily take off to try and fail rolls) you could make it switchable, usually on, "costs fatigue", try to "power block" with it and fail, etc...

Originally Posted by Rupert

I don't think the Magic Resistance is a very useful thing to put in as part of the 'mage build'. Anyone could have it, not just mages, and it doesn't make a mage better at magic.

Magic Susceptibility OTOH would make it very each to practice casting spells on yourself :)

Originally Posted by Rupert

unless you're confident you'll never need magical help from outside yourself you'll want that Magic Resistance to be Switchable (+10%) - it only costs 2 points, so why not?

T63 sets it at +100 like damper/enhancer for mages, just like P59 set Discriminatory for them as same value as B67 "Improved" for MR.

Though it's +10% for non-mages so maybe you mean that

Originally Posted by AlexanderHowl

Magery does not allow for the development of Immunity (Magic) (Powers, p. 111)

P111 is new limitations, were you thinking of P131?

Resistant isn't a listed example there if that's what you mean?

Originally Posted by AlexanderHowl

and specifically forbids in on Powers, p. 72 for magical systems that require the channeling of magical energy.

"often the case" sounds like there could be exceptions...

and P72 mentions "a power" providing protection against it's source should be forbidden, but that wouldn't prevent you from having "Immunity to Magic (Psionic Telepathy -10%)" as 1 power and a separate batch of magical powers.

M12 similarly talks about powers protecting against their source, so Immune to Magic as a wild advantage (not a power, no source) would not clash with having Possession (Magical -10%) or similar.

The interesting thing about magic is also that when you can resist, you can voluntarily waive resistance rolls, so you could take the +8 resistance and opt to waive it in cases where you trust the caster. I just don't know if the auto-success version is waivable in that way.

Originally Posted by AlexanderHowl

Immunity (Magic) effects all magic.

P72 "Resistant and Immunity only help against threats that offer resistance rolls"

Worth wondering if something "offers a resistance roll" in the situation of "I'm consenting to the spell".

Originally Posted by AlexanderHowl

Immunity works against effects of that type that do not allow for Resistance rolls (for example, Cyanide for Poisons

Are we told somewhere about this explicitly for cyanide?

B439 makes it sound like a "direct physical attack" (ie Toxic Attack) since it would lack the "Resistible" limitation.

This can be respiratory, matching "Innate Attacks with these modifiers" on B80.

We're told it doesn't apply where DR does, but since respiratory ignores DR that's no help... "do not have any any of the modifiers given above" and so forth.

I guess maybe I'm wondering what the point is of DR (poison only, hardened) would be if ITDR does that, but I guess it would still be "forms of poison that don't ignore DR".

Contact agents having a 15 minute delay is something I'd have trouble putting in Innate Attack terms... I guess it's like Onset / Exposure Time

Maybe "Resistible on a HT-20 roll" would be like a -0% limitation and what things like this effectively are? It's just a strange jump to go from Resistant to Poisons +8 doing nothing (nor a Power Block doing +16) to the next step being a guarantee.

Sort of like how P118 "Instant-Death Attacks" treats an HT-18 affliction as "instantly kill anyone with HT 20 or less" even though an effective HT of 2 is actually still supposed to let you have a resistance roll.