A discussion I actually had with my girlfriend recently, how Ring durations affect light and flowing substances. Thought I'd post it here for more input, from people who know the books and canon better than I do. Can light or water cross the edge of a ring that sustains it? The ring supposedly is 'broken' if the target passes beyond the edge of the ring.
Situation one: CrIg Create light, D:sun. It creates a point of light, shines and fills a room. Nobody has any problems with how this works.
Situation two: CrIg Create light, D: Ring. Theoretically, this spell lasts forever until the ring is broken. however, you're creating a light, the target, which is filling the room. I'd never doubted it til now, but it feels like the substance of the light is implicitly expanding beyond the ring and breaking it.
Situation three: CrIg Create Fire, D: Ring. An expansion, this creates a small bonfire inside the ring. This is a physical object, and sheds light and heat naturally. The byproducts should be able to pass the ring safely, but as long as the actual fire stays where it is, the ring won't be broken.
Situation four: CrAq Create Water. If you feel Situation Two should still work, with a permanent light, what if instead you create water in the circle? Like light, water expands fluidly to fill an area, but is a more physical object than the light. I assume this would break the ring if it flows out beyond the circle.
I feel like I'm just rambling at this point...
Apparently the ArM5 p.113 size of Creo-ed light is determined by the space it illuminates: see ArM5 p.139 Moonbeam and p.140 Lamp without Flame. Being seen from outside a Ring would then not qualify for breaking it, but illuminating an area beyond - i.e. triggering and transporting (HoH:S p.61) iconic species there - would.
This requires an on/off understanding of illumination, of course. But as your eyes adapt to the light, the area it illuminates for you is usually well delimited: and comparing different people's vision to exactly determine the boundary of the light you Creo-ed is sooo 18th century.
A water target flowing out of the Ring clearly
the Ring, ending the D: Ring spell.
2A - CrIg create light spell with D: Conc plus a D:Ring ReVi spell to sustain it? Would this work and would it be different than 2?
AFAICS the D:Ring ReVi spell to sustain it requires a thorough troupe discussion.
Just when would its target - here the D: Conc CrIg spell - move outside the ring? When would other possible target spells, like a D: Conc version of ArM5 p.117 The Wizard's Mount?
Once spell A is cast, in documented magical practice its location is no longer distinguishable from the location of its target:
- Dispelling A targets A's target.
- InVi spells to detect A locate it on A's target.
- An Aegis reacts to A if A's target moves into it.
Does this hold in general? It certainly makes sense also for the D:Ring ReVi spell to sustain A.
I mostly added the flowing water example as a show to why I felt the light moving beyond the ring would be considered breaking the ring. Treating light as a fluid seems somewhat... mythically appropriate.