Cloudkill and other moving spells

[Ravingdork]

Does cloudkill stop when it hits a wall or other impassible barrier? Can it be contained? Or does it just keep going no matter what because magic?

Does it keep moving straight, or does it follow along the ground, sinking to the lowest level, such as down a set of stairs into a basement?

How are other spells that move intended to be effected by the environment?

[Laran]

Since there is no description as being heavier than air or rolling on the ground (like PF1 version), it definitely travels 10' but the direction could be straight up and it would not fall back to earth. It also does not say in a line so you could also have it turn so move 5' forward then 5' left. Next round 5' forward and 5' down.

It is a conjured substance and has the quality of poison so I have to guess that it is a physical not psychic manifestation. If that is the case, it should be stopped by physical barriers.

Interesting - Should Gust of Wind (a level 1 spell) be able to neutralize Cloudkill (a level 5 spell) since Gust says it disperses fogs and mists. I have to assume they meant Gust of Wind disperses non-magical fogs and mists

*edit*

One thing I have noticed is that the new edition has parts of rules spread across the book so you have to look in three or more places to understand the rules. I would not be surprised if there is some trait or ability description where we would not think to look that has a line pertaining to this type of effect

[Mathmuse]

My players have a question about Cloudkill and reviving this thread seems better than starting a new one, because Ravingdork's original question matters, too.

Cloudkill wrote:

You conjure a poisonous fog. This functions as obscuring mist, except the area moves 10 feet away from you each round. You deal 6d8 poison damage to each breathing creature that starts its turn in the spell's area. You can Dismiss the spell.

When the Cloudkill movers away from the caster, does it change direction if the caster has changed position? For example, imagine the caster cast Cloudkill south of herself, so at the beginning of her turn it moves 10 feet southward. But on her turn the caster moves west of the Cloudkill. Next turn, will it continue moving south as it had done before, or does it move eastward away from the caster's new position?

The party is about to face an army of hundreds of hobgoblin soldiers in Assault on Longshadow. The fey-blooded sorcerer Honey wants to further weaponize Cloudkill by getting it to move in an unpredictable curve through the army.

[Castilliano]

The spell could be read as if "you" alters with your new position, but it seems much more like a "fire and forget" spell that keeps rolling out in the direction launched; the "you" being only in regards to the time of casting.
There doesn't seem to be any sort of link to justify it altering course.

[Ascalaphus]

It could be either one, the text is legitimately open to multiple readings. And depending on the needs of each particular combat, either reading could be good and bad in some of them.

Choose something and then be consistent about it :)

[breithauptclan]

First, I second the idea from Ascalaphus: pick a ruling and stick with it.

Mathmuse wrote:

The party is about to face an army of hundreds of hobgoblin soldiers in Assault on Longshadow. The fey-blooded sorcerer Honey wants to further weaponize Cloudkill by getting it to move in an unpredictable curve through the army.

Second, as the distance between the caster and the cloud increases, the difference between the rulings becomes less noticeable. The caster is going to have to move an incredible amount of lateral distance in order to get the cloud to move in a noticeably different direction.

https://mathbitsnotebook.com/Geometry/Circles/CRArcLengthRadian.html

Arc length is approximately the same as the lateral distance needed for large radius circles.

Arc = (degree change desired) / 360 * 2 * pi * (distance between cloud and caster)

So at 60 feet away, if you want a 45 degree change in direction, you would have to move 47 feet.

At 120 feet away, if you want a 45 degree change in direction, you would have to move 94 feet.

And I just noticed that I am telling Mathmuse this.