Gaseous Underwater

[Burley]

I'm a wizard in a pirate campaign and we explore the ocean floor frequently. This may become relevant in the future:

If I am underwater with a willing creature and cast Gaseous Form on them, would they become a conscious bubble and immediately float to the surface? What's the density of "gaseous?" How deep would we have to be for the water pressure above us to hold them down? Would they avoid the bends because they don't have organs during the accent? Would their movement speed still be 10ft, which seems slow for a bubble?

I know, I know. "It's up to my DM." But, c'mon, play in this space with me.

[Keltest]

I would say either it functions identically to in air, or you become immobile because you can't interact with the water to displace it for movement, depending on how punishing you want "being underwater" to be. Mostly I would probably use the first option at my table.

[Reynaert]

The spell description of gaseous form has the following text: "... it treats liquids as though they were solid surfaces ..."

So I guess by RAW they'd be stuck as if they were encased in rock.

[Burley]

The spell description of gaseous form has the following text: "... it treats liquids as though they were solid surfaces ..."

So I guess by RAW they'd be stuck as if they were encased in rock.

I don't disagree, but it may read like I do.
Air bubbles already function that way. It's the water that moves around the air bubble, with surface tension acting as a solid wall. The water is raising the less dense "solid" object up.

I didn't even think of this, either: Is the density of salt water such that it could explain Gaseous Form functioning as normal?

[Segev]

Because the spell goes out of its way to say you can't enter liquids (the "treat liquid as solid" clause), I would rule personally that it makes you boil up to the surface and then you're stuck up there until you turn solid again and thus can choose to enter the liquid once more.

If you have an ability - such as Incorporeal Movement - that lets you move through solids, you could move through the liquid. But if you do, and end your turn inside it, you take damage as per that feature's statement about ending your turn inside solid objects.

[Burley]

Because the spell goes out of its way to say you can't enter liquids (the "treat liquid as solid" clause), I would rule personally that it makes you boil up to the surface and then you're stuck up there until you turn solid again and thus can choose to enter the liquid once more.

If you have an ability - such as Incorporeal Movement - that lets you move through solids, you could move through the liquid. But if you do, and end your turn inside it, you take damage as per that feature's statement about ending your turn inside solid objects.

I don't think that ability would come into play, since the spell specifies that it can't affect incorporeal creatures.

[Segev]

I don't think that ability would come into play, since the spell specifies that it can't affect incorporeal creatures.

Which is actually an amusing bug in the rules. There's no such thing as "incorporeal creatures" in any defined sense. That'll be a DM call. Some creatures have "incorporeal movement" without being always incorporeal. They kind of shift back and forth. The Fractal Mascot comes to mind, especially as something the PCs might have on side and want to buff.

[JLandan]

Too much physics is not good in D&D.

That being said, I would call it that the gaseous form would be immobile under its own power, unless it has some magical (rather than physical) swim speed. Flying speed don't cut it. This is due to liquid being treated as solid.

However, because the gaseous form is less dense than the surrounding water, it would float to the surface, but this movement would be uncontrolled.