Cloudkill movement ...

[jgsugden]

From the SRD:

Unlike a fog cloud, the cloudkill moves away from you at 10 feet per round, rolling along the surface of the ground.
Figure out the cloud’s new spread each round based on its new point of origin, which is 10 feet farther away from the point of origin where you cast the spell.
Because the vapors are heavier than air, they sink to the lowest level of the land, even pouring down den or sinkhole openings. It cannot penetrate liquids, nor can it be cast underwater.

My questions:

1.) What happens when the cloud has no place to go? If its path of movement takes it into a dead end, does it remain in the dead end, or does it try to be centered inside of the wall of the dead end when you recalculate the area, resulting in the spell ending?

2.) The spell specifies that it moves away from the caster. It doesn't say that it moves away from where the caster was located when he cast the spell. What happens when the caster moves? Does it move away from the caster's new location, or the spot where he cast it? The wording seems to indicate that it will move away from the caster's new position ... Which brings up the question of where the cloud will go if the caster is inside the cloud.

3.) The cloud sinks to the lowest point available, but it moves away from the caster as well. What happens when these are in conflict? If a wizard standing at the bottom of a slops casts the spell at a point along the slope, does the cloud move away from him up the hill or does it move back towards him by sinking to the lowest spot possible?

How about some input, folks?

 

[Flyspeck23]

1.) What happens when the cloud has no place to go? If its path of movement takes it into a dead end, does it remain in the dead end, or does it try to be centered inside of the wall of the dead end when you recalculate the area, resulting in the spell ending?

Tough. Could the cloud pass through solid material? Might be, as the description only talks about liquids. Either the cloud keeps moving or it stops - I don't think the spell will end.

2.) The spell specifies that it moves away from the caster. It doesn't say that it moves away from where the caster was located when he cast the spell. What happens when the caster moves? Does it move away from the caster's new location, or the spot where he cast it? The wording seems to indicate that it will move away from the caster's new position ... Which brings up the question of where the cloud will go if the caster is inside the cloud.

This isn't supported by the wording, but I'd say the intention of the rules was that the cloud keeps moving away from the original position of the caster. Otherwise the spell IMHO get too potent.

3.) The cloud sinks to the lowest point available, but it moves away from the caster as well. What happens when these are in conflict? If a wizard standing at the bottom of a slops casts the spell at a point along the slope, does the cloud move away from him up the hill or does it move back towards him by sinking to the lowest spot possible?

As there seem to be some "laws of physic" involved, IMHO the cloud would move to the lowest point - the caster only gives direction, and if that direction isn't the most logical way for the cloud (uphill vs downhill), the cloud'll move elsewhere.

 

[dcollins]

(1) It stops in place (ceases moving) if it has no place to go. For example, when it hits the bottom of a sinkhole it sits there for the duration.

(2) It is moving away from the point where it originated. As you quoted, "Figure out the cloud’s new spread each round based on its new point of origin, which is 10 feet farther away from the point of origin where you cast the spell." You can't run to the other side and make it change direction.

(3) Sinking in elevation takes priority.

 

[jgsugden]

I'll agree that it should move away from the point of origen. There is contradictory language, but I think the likelihood is that it is intended to move away from the point of origen.

I'll also agree that the cloud will hang out in a place if it has run out of places to go. Perhaps it will slowly work its way under a door if one is present, but in general, if it reaches a dead end, it should stay there instead of being negated by trying to be recentered inside a wall.

As for the battle between moving away and sinking, why do we assume that sinking takes priority over moving away? Moving away is listed first. I think that would be at the highest priority. Thus, I would let the spell go down and forward, but never to the side or backwards, even if backwards would be down a slope. As a creation spell, magic does remain to guide it, so having it not move backwards does make sense, even when it would be moving down a slope.

Thoughts?

 

[mikebr99]

Well...we could break out our Trig books... mass, velocity, friction... gravity, slope... oh, it's been so long...

 

[jgsugden]

Well...we could break out our Trig books... mass, velocity, friction... gravity, slope... oh, it's been so long...

I tried all my science and math books. My book was missing the chapter on the effect of magic on gaseous structures.

The spell is moved by magic (as there is no nonmagical reason for the cloud to move away from the caster's origen spot at a consistent rate). Once magic becomes involved, mathematics is questionable at best ...

 

[Scion]

It is just a constant force problem those exist in mathematical terms.. so it will push against the wall, just treat it as a slow moveing, but somewhat dense, fog. If the wall is a lightweight it might be able to push through (fly paper wall anyone?) otherwise it will push against the wall, the wall will push back, and they will give one another mean looks until the spell duration ends

Personally, I would treat it like a big rolling could donut (no hole, or a weird pancake I guess). If there is a way it can get around barriers, or even roll over them, then it probably will. If part of it gets stuck then that part will dissipate as the rest of the donut moves past and then reform if able. In other words, if it fell down a hole, hit the bottom and had nowhere to go that would end that part of the spell. Any round when it should move, but cant, that part is gone. (moving 10' down a hole would still be 'away', no need to break out the protractors and compases!)