I am considering the following spell/effect for a Muto specialist:
How would you treat this with regards to magic resistance? I would tend to assume that it is completely bypassed. The fog cannot sustain a creature's weight so it falls. Damage from falling is on natural surface at the bottom of the pit. When the fog turns back into natural dirt to stone, it isn't magical anymore so the burial isn't resisted.
The spell might require an Aiming roll, but unless it is done on a stone surface it is unlikely to fail (even though the magus in question has Clumsy Magic).
That seems contrary to canon, as a magus can walk on a bridge created by magic but will slide between magically created spikes (ArM5 p.86). The magical fog would move around the magus without touching him, but the magus cannot walk on it IMHO.
It's there, right after the spell's parameters.
Indeed, I mention the possibility of needing an Aiming roll. As per ArM5 p.86, the size increase would give a +12 bonus to the roll, although it would make sense to reduce that to +6 when the ground is stone (due to the smaller size of the hole). This is unlikely to miss, even for a magus with Clumsy Magic.
Magic resistance would not protect the magus, at no point is he being worked upon by the magic, there is nothing to resist. When the fog turns back, the mage would be surrounded/buried by the earth/stone. Suffocation would become an issue and depending on how deep the pit is they might get crushed by the weight above them.
I agree with GribbletheMunchkin that MR would be completely bypassed.
One thing that's not entirely clear, however, is how quickly the transformation will take place. You seem to assume that it will be literally in the blink of an eye, but by the rules it could still require two or three heartbeats during which the earth progressively dissolves, so that the victim is deposited at the bottom of the pit unharmed. This is a troupe decision. Remember that T:Part +2 size affects 1000 cubic paces of dirt, so if it's in the shape of cylinder 15 paces in diameter, it's about 5 or 6 paces deep.
I disagree with GribbletheMunchkin about the earth/dirt crushing anyone buried underneath when it reforms. Earth, sand and the like weigh little more than water, per unit of volume, maybe half-again as much. Being 4-6 paces deep in dirt is then like being at a depth of 6-9 paces in water, which is no big deal.
The victim(s) would definitely be entrapped, however, and suffocation would become a problem ... after several rounds. Of course, if you are the victim and a magus (and you did not manage to fast cast a defense) it only takes a first magnitude Muto, Rego or Perdo Terram spell to free yourself.
Finally, note that if the caster is standing on a nice field of lush grass, it maybe hard to target a patch of earth beneath the grass a few dozen yards away; and that trees, small buildings etc. in the target area might help victims avoid falling in and/or pose a hazard to the caster.
Fair point. With MR rules having contradictory applications (pink dot) I often take the approach that it will protect the defender from an effect. I know that's a very broad view but the MR rules are fairly wobbly in a few circumstances.
Since the transformed dirt is a gas, it should be displaced by whatever solid moves through it.
Magic Resistance should prevent you inhaling any of the gas, so the difference would be whether or not the trapped person's lungs are filled with dirt when the spell ends.
Also note, that some breathable air around the being with MR is also protected by it (ArM5 p.85). So, also turning the earth to non-breathable or even to poisonous gas does not affect a victim with MR immediately.
Such spells look like a means to make a magus really mad, and have him assume forfeit immunity of the caster at once.
As a storyguide, I would allow some kind of Quickness + Athletics roll for a character to escape from the closing pit (if not incapacitated) considering that the Muto effect won't necessary end instantly. I tend to think that Momentary effects take a few seconds to vanish completely, hence the possibility to escape.
To me, a spell that effect closes instantly in such a way there is no chance to escape would require one more magnitude, similarly as the "fancy effect" of the Earth Split Asunder (ReTe 30 corebook).
Funny how people seem to assume that such a spell is intended to attack another magus. In my initial questions, I specifically mentioned a "creature", not a magus.
The question of how quickly the transformations take place is a fair one. But considering that the effect has a duration of momentary, it would not make sense for that to require "two of three heartbeats", unless the magus' wizard sigil is that changes occur gradually or he has a flaw such as Slow Magic. In this case, the magus' sigil is "the target deforms temporarily", so the ground would seem to move and bulge for a second before transforming into fog. After perhaps one heartbeat those within the area would find themselves standing on a surface that can no longer support them and they would fall, as stated by the spell's description. The spell was designed for this, and I think the magnitudes added for size preclude a target near the center of the effect from being able to make a roll to avoid the fall, barring supernatural capabilities. The spell already requires an Aiming roll, after all. Allowing a normal target a roll to avoid the effect seems like double-dipping.
I agree that the reforming ground would not crush those trapped inside the pit. They would, however, be essentially immobilized. So activating an enchanted item or digging themselves out would range from the very difficult (in loose ground or sand) to impossible (in rock). A trapped target with magic resistance (such as a magus) might still be able to speak, because the fog was kept a little distance from them when it reformed, for if the ground is soft it will quickly settle on them so it might become impossible after a round or two. Suffocation would start after a few more rounds.
I've seen the suggestion that it is not possible to target the ground that is beneath grass or similar non-Terram ground coverings. I personally think that in most cases it is hogwash. Sure, if the grass is several feet long you might not be able to gauge where the ground is. But the caster himself is standing on it, so he knows how deep the grass is and where the ground is. He also sees those within the target area and how they are partially obscured by the grass. IMHO he can still target the ground. The Limit of Arcane Connection mentiones that you cannot affect an unsensed target without an arcane connection. "Unsensed", not "unseen". Being yourself on the ground certainly allows you to sense its presence a few dozen paces away when you can see the surface of the grass.
Now, the presence of a dense and solid root system in the target area might allow those within it to soften their fall or even prevent them from more than sagging into the pit. This might result in only partial burial when the ground returns. But again, those are special circumstances. I expect any SG worth his salt to use his judgment on that. Just like I would expect the SG to say that a Pilum of Fire is less effective (and perhaps not at all) when cast under water.
Now, if one of those standing in the target area is a magus, there are indeed all kind of spells he can use to avoid the pit though fast-casting, or to get out of it when the ground reforms. The question of forfeit immunity is irrelevant. Yes, this is a magical attack if it is aimed at a magus. Yes, it might not be effective against an experienced magus with the appropriate spells. That's not what I'm interested in discussing.
I would point out that turning the stone into a gas, and then letting someone fall through it will leave the ground thoroughly rearranged when it returns to normal, and there will be noticeable mixing of gas where the person fell through. And unless you're in a desert or wasteland you'll probably have a bunch more crap getting in the way, or ripping through the gas.
Sure, it would leave a mess on the surface if things fell through the fog. Not a good idea to cast that spell within your covenant's council chamber if you want to keep your nice floor.
Do you feel that an Herbam requisite would solve at least part of that "bunch of crap getting in the way" problem? I think that this might even be satisfied by the fairly frequent statement in Terram spells that "Casting requisites are required for the appropriate Form for the target." The spell does a fairly simple thing, after all: change the ground into fog. Bones, metals and such are unlikely to cause a problem; they will just end up at the bottom of the affected volume of ground.
One important question is just how long is a moment? Is it as long as a second? A half a second? Less? More? Is it just the blink of an eye? Because it takes time for a body to fall (about 3/4 of a second to fall ten feet if my back-of-the-envelope calculations are correct).
Now, 3/4 of a second isn't very long, to be sure. But is it longer than a "moment?" I think that's an interesting question for the troupe to consider.
Actual the entrapped might also not work that well because the fog is pushed away when the person is falling in and is at last partial replaced by air coming from above.
As Trogdor mentioned much depend how fast a moment is if it is 1 second or less then it might be just enough to get someone running to struggle for balance because (s)he unexpect hit no ground with one step.
Also someone falling trough the fog might never reach the ground before the moment end and so there is no falling damage.
Edit: reading trough the spell "THE EARTH SPLIT ASUNDER" ArM5 156 again I would say that the +1 fancy effect and the 3 round concentration is needed for this spell as well to work as intended.
If you look at examples from the corebook, you'll see that D:Mom can mean up to a round (i.e. half a dozen to a dozen heartbeats), and many D:Mom effects don't just happen in the blink of an eye, but take a few heartbeats. So, I think it's fair to say (as I said) that this aspect of the spell should be negotiated with the troupe!
I may be weighing in late here, but I'm of the opinion, any aware creature would have a chance to react to the change, to varying degrees of success. I don't think someone in that time could climb out of the pit they fell into, but by they might end up making enough of a pocket that they can try to dig out after the spell's momentary duration. Similarly, having a body fall into a gaseous pit will displace a lot of the gas, and it won't naturally want to reassert itself into the pit (similar to how Rock of Viscid Clay doesn't return to its original shape after you mold it), so when the spell ends, you're going to have gaseous-fountains of dirt or stone and probably pockets of air under the now-sealed stone/rock. Casting it in a grassy field would leave a mess of grass and roots mixed into the stirred-up soil-gas, which would make it harder to dig out, and tree roots make it less likely for a person to fall to the bottom.
A related question, for clarification on spell guidelines: Does the +1 magnitude to upgrade it from dirt to stone allow it to affect both in full? The spell guidelines don't explicitly state... bit it would be dumb if your wall-of-dirt can't get destroyed by a PeTe Shatter The Wall. If I have a spell that summons a wall of stone above someone's head, can I just have it be a wall of dirt instead?(That seems silly) if I have a spell that digs a grave-sized hole in solid stone, it should work in a dirt field too, right? If I cast it in dirt, does the size of the hole increase?
That's what the Aiming roll is all about. Of course, because of the size of the area affected, those in the target area may have very little ways that they can react effectively. They may have a second or two to react, so if they are near the center of a 15-pace hole, there isn't much they can do except prepare for the fall (i.e. an Athletics roll to reduce falling damage).
This is of course different if we are talking about a magus, as his range possible of actions is far broader.
That very much depends on the exact circumstances of casting the spell, of course. An extensive and dense tree root system may allow some of those in the area to only sag down a few feet instead of falling to the bottom, in which case they would only be partially buried. There might be pockets of air formed as they fall down, allowing them to breathe a little longer before suffocation begins, giving others time to dig them out. But I doubt they would be able to dig themselves out without help without it being a mythic feat or using some sort of supernatural power.
The main point is that this is not meant to be a fool-proof, auto-kill, bypass-magic-resistance spell. But unless one is lucky, prepared or has appropriate spells to save themselves, then the most likely result will be death by suffocation. Of potentially multiple targets.
Creo spells tend to be quite specific about what they create. Muto, Perdo and Rego spells tend to be much more flexible (though not always), if you look at the canonical examples. It very much depends on the exact effect being sought. For example, Rock of Viscid Clay turns stone into clay, not sand into clay or stone into sand. Its description is specific and clear. Fist of Shattering, on the other hand, specifies that it shatters an object of stone or weaker, even allowing one to use Form casting requisites to affect objects composed of a material outside of Terram. As such, it attacks the Terram-ness of solid objects, rather than the nature of the objects themselves.
In the same way, I think that it is perfectly reasonable for a spell that turns the ground into fog to affect both earth, sand, mud and stone. If targets a solid stone floor, a smaller section of the ground will be affected, reducing the bonus to the Aiming roll that the extra Size gave the caster.
