Magical null zone, powers, and penalties

[Fandraen]

During city creation, my players came up with the idea of having a particular area be a magical null zone, a la the

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aquarium during the Denariians' Archive kidnapping attempt

; part safe zone (there's not as much power available here), part prison. I thought I'd ask around and see if folks here had any good ideas for how to run a location like that.

1) External magic sources are cut off; you have what you came in with. How would this operate in play? A limit to how many shifts of power worth of spells you can cast? And if so, how would one set a reasonable default limit, and a reasonable "You can pull in a little bit of extra power, but you'll be casting dangerously until you bleed the excess off" effect? For the second, I'm inclined towards a variation on "you can pull in up to your conviction extra shifts of power, or roll to draw in power and control it a la thaumaturgy but without the spell; all spells that you cast have an added difficulty of the extra shifts of power you have stored over your normal threshold"; it makes holding more than a few extra shifts of power really, really dangerous, but it's possible if you're desperate. What I don't have is any idea what a reasonable base threshold ought to be.

2) Some powers probably shouldn't work as well there... but which ones? Sponsored Magic being right out unless you prepared the spell in advance would make sense. How about faerie glamours that create things out of ectoplasm pulled from the Nevernever? Or other shapeshifting, ditto? Which magics are inherent (and therefore preserved), which are penalized, and which ought to just be out of the question?

3) How do I create a feeling of "Magic is hard here?" For an actual mage, limiting the amount of power they can draw or making all spells more expensive (for more of a low-level anti-magic-field than an actual hard cut-off) seems pretty reasonable. But for powers that don't normally have a roll (like shapeshifting), what do I do? I can add an aspect to the location easily, but that will only help people trying to take advantage of it; it won't make life harder for everyone else. And... should it? Or is this really something that ought to just be color?

[wyvern]

1) I'd say you have, by default, total shifts equal to your conviction (maybe half that if you just wandered in without realizing what you were walking into).  If you pull in more power, it functions like thaumaturgy; you call up power, and roll to control the number of shifts you added this exchange.  Using power would be the same - just roll to control the number of shifts you're using.  Except that, like thaumaturgy, if you *fail* that control check, you're looking at backlash or fallout based on the total shifts you've got available, not just what you thought you were putting into the spell.

2) Sponsored magic is right out unless you've got the sponsor with you, or otherwise have a reservoir of power on you.  Glamours would mostly work, I'd think, but true seemings (i.e. ectoplasm based stuff) wouldn't.  Some shapeshifting would work unimpeded; the Alphas, for example, insist that what they do isn't spellcasting so much as a sort of a mental switch.  Other shapeshifting, like, say, hexenwolves, would suffer threshold penalties to all actions, or just fail entirely.

3) Adding an aspect is a good idea; you just need to remember to compel that aspect when appropriate.  Other than that, like a threshold, you can just start adding penalties to all affected rolls.  On the other hand, this might also be sufficiently covered by items 1 & 2; it really depends on if this place just doesn't have power you can draw on, or if it actively leeches power out of things...

[Ophidimancer]

I guess you could just put a Ward on the place and make it so that no one is considered invited.  This basically means that anyone trying to cast magic has to summon more than necessary in order to accomplish anything.  This makes magic more tiring, accomplishing number 1 and number 3?

[Ophidimancer]

Of course, I am away from my book at the moment, so I might not be remembering how a Threshold works correctly.

[Fandraen]

Ah, hey. The "Threshold no one is invited to cross" might actually cover a lot of what I'm looking for. I'll have to go take a look at what exactly that does.

And decide whether it stacks with my faith-based chars. (I think the answer is "No", officially a threshold or not.)

[Belial666]

Power equal to your conviction alone does not work; both Dresden and everybody else who cast was using pretty major spells in there more than once. How about this;


Power-insulated zone:
The area is cut off from external power flow.
  * External sources of power such as Faerie Magic, Spirit Magic and other forms of external sponsorship can no longer offer sponsor debt. The caster can still use magic with his/her own energy - but see below.
  * There's a finite amount of energy in the area equal in total shifts to the number of humans (or equivalent life-force) living within. Once this power is exhausted no more power can be drawn and any abilities that require shifts of power no longer work.
  * A spellcaster can prepare and draw in all the power he wishes to use ahead of time. He needs to pre-pay all the mental stress (including consequences) in advance and he needs to make control rolls for gathering that power as if for a ritual. He still needs to make separate control rolls for each spell later. He can hold that power for a number of minutes equal to his base conviction - after that he has to release either as backlash or as fallout.