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Leecros
2010-11-07, 09:53 AM
All right. Last night i was at my weekly group of Dungeons and Dragons and the DM decided that he would put us through a water dungeon. We're in the middle of the ocean and he recently discovered Dungeonscape. So we go into a room and trigger a trap that dispelled the way in/out of the room. So now we're stuck in...basically a bubble and that's where the DM ended it.

He packed up and left and the rest of us stayed and discussed how we were going to get out of this bubble. So the idea came up of just dispelling the magic holding up the room and swimming to the surface....because the DM said that the surface wasn't too far away. We were discussing the chances of drowning and other dangers to that when the one person chimed in; He's a Warforged, if anything happens he can just sink to the bottom and walk out.

Now we're in the middle of the ocean, Ignoring the likely possibility of him being eaten by a giant fish, we weren't told the depth, but since we don't know we can figure that it can be up to 6 miles, most likely less, but that's probably the worst-case scenario. So one of the guys says that if the pressure didn't crush you then it would be so strong that you wouldn't be able to move. His retort was that 'if we were using real world physics then mages' hands would be burnt and blistered from fire spells' So he hasn't read any rules on it, thus he feels that water pressure doesn't exist. That's my take on his response.

So after several minutes of arguing i finally get tired of it and say that i'll go home and look up some rules on water pressure. I've been looking everywhere i can think of and i simply can not find any definite ruling on water pressure.

So last resort i'm bothering you guys. :smallwink:

Are there rules on water pressure? If so do you know what book or books it would be in? If not what would be a good set of rules for it?


Thankee in advance :smalltongue:

Saph
2010-11-07, 09:58 AM
There are in fact rules for water pressure. They're in Stormwrack, page 11.

Without copying the entire text, the short version is that you take a dice of damage every minute for every 100 feet beneath the surface. A Fort save holds off the damage, but the DC gets higher and higher the longer you stay down there.

Having the aquatic type reduces the damage considerably, and being a deep-dwelling creature like an whale or an aberration, outsider, or elemental with the water subtype makes you immune to it.

Leecros
2010-11-07, 10:02 AM
There are in fact rules for water pressure. They're in Stormwrack, page 11.

Without copying the entire text, the short version is that you take a dice of damage every minute for every 100 feet beneath the surface. A Fort save holds off the damage, but the DC gets higher and higher the longer you stay down there.

Having the aquatic type reduces the damage considerably, and being a deep-dwelling creature like an whale or an aberration, outsider, or elemental with the water subtype makes you immune to it.

all right, that is excellent. Thanks!:smallbiggrin:

Psyren
2010-11-07, 10:04 AM
I would houserule that to apply to constructs as well. I don't see a reason why a golem or warforged couldn't just take on water to equalize the pressure and strut around at the bottom, Big Daddy-style.

Last Laugh
2010-11-07, 10:05 AM
Blackwater domain grants immunity too!
(warforged+blackwater domain would be a fun character)

Malbordeus
2010-11-07, 10:15 AM
this doesnt however cover the issues attached to said depth of water falling on you when you dispell the bubble...

dump a swimmingpool of water on somone from100 feet and the question about water pressure becomes fairly academic.

then theres the 'bends' if they surface from the ocean floor too quickly. but again, these issues i figure will be largely academic too after water cascading on them and the pressure.

Leecros
2010-11-07, 10:35 AM
this doesnt however cover the issues attached to said depth of water falling on you when you dispell the bubble...

dump a swimmingpool of water on somone from100 feet and the question about water pressure becomes fairly academic.

then theres the 'bends' if they surface from the ocean floor too quickly. but again, these issues i figure will be largely academic too after water cascading on them and the pressure.

hmm....important point. After all this, in hindsight maybe dispelling the bubble is a bad idea....:smalleek:

Greenish
2010-11-07, 11:49 AM
Blackwater domain grants immunity too!
(warforged+blackwater domain would be a fun character)Also available as a feat via Planar Touchstone.

Malbordeus
2010-11-07, 02:31 PM
i think planeshifting out, or jumping into a bag of holding and attaching floats before evac'ing through the wall might be the safest plan. :P

Psyren
2010-11-07, 04:47 PM
i think planeshifting out, or jumping into a bag of holding and attaching floats before evac'ing through the wall might be the safest plan. :P

You could also just become incorporeal or ethereal. Water Walk will zip you to the surface but then you might get the Bends.

Leecros
2010-11-07, 05:02 PM
Water Walk will zip you to the surface but then you might get the Bends.

i think 'might' is out of the question there.....Will get the Bends you will by doing that...:smalltongue:

Yora
2010-11-07, 05:31 PM
Depending on the terrain, it could be possible to go around the water by going through the ground. Magic that allows you to move through solid rock doesn't care about the pressure around the rock. If the rest of the dungeon is still dry, you could reach it safely within a few minutes or less.
If going through the earth isn't possible, you might create a new passage to the rest of the dungeon and somehow reduce the water pressure only inside the tube. Rock shape or something like that would work here.

I take it you don't have any way to teleport?

137ben
2010-11-07, 07:56 PM
If magically tunneling through rock ignores pressure, then it seems like water walk would bypass water pressure as well. I don't have stormwrack, though, but it seems like that would make the most sense.

blackjack217
2010-11-07, 08:21 PM
Does he even have stormwrak or is he even using these rules?

Tvtyrant
2010-11-07, 08:26 PM
i think 'might' is out of the question there.....Will get the Bends you will by doing that...:smalltongue:

Actually you wouldn't. The Bends is based on a length of exposure, not only depth. If your down for only a few seconds the nitrogen in your blood will not be able to become liquid, so it won't form bubbles when you go back into a low pressure environment.

In fact there is a sport based on this fact where you grab a rock, jump into the ocean, go down as far as you can and let go of the rock and swim like hell for the surface. Can't remember the name but they have beaten the depth records of people in scuba-suits because of this.

The problem is that the bubble itself would be pressurized in real life, so you would already be under its influence. But its magic afterall.

BridgeCity
2010-11-07, 10:18 PM
If magically tunneling through rock ignores pressure, then it seems like water walk would bypass water pressure as well. I don't have stormwrack, though, but it seems like that would make the most sense.

Waterwalk allows you to walk on water. Stonewalk spells allow you to walk through stone. There is a massive difference in what each spell is attempting. It makes sense to build resistance to being crushed by stone into a spell that puts you inside stone, it doesn't make sense to build resistance to being crushed by water into a spell designed for you to not go into the water.

dgnslyr
2010-11-07, 11:26 PM
Hmm, if Stonewalk lets you walk through stone, which may or may not be denser than water, *cough*pumice*cough* then it would make sense that it lets you go through water while ignoring pressure changes. That's actually pretty interesting.

RndmNumGen
2010-11-07, 11:32 PM
This might actually depend on what the inside of a warforged is like. Could it be filled with water and not cause damage to the warforged? If so, water pressure shouldn't really apply, because it's equalized(same pressure inside as outside). It's only when you have less pressure inside than outside that it becomes a problem.

ShneekeyTheLost
2010-11-07, 11:44 PM
Every time you bring RL physics into a D&D game... well, you know the meme.

No, there are no rules for the 'bends', and Warforged, who don't breathe, wouldn't get them anyways.

Honestly, people. Either Water Walk or simply Teleport to the shore. It should very easily be within range of a Teleport, depending on how far down your bubble is, it might be within DimDoor range. It's really not that complicated.

Psyx
2010-11-08, 09:55 AM
Dropping a 700m column of water on your head if you dispel the bubble would certainly be good for 20d6 damage (no save) in my world, regardless of pressure issues.

There are no formal rules for pressure that I'm aware of, although there is mention of pressure in a clerical domain. There's also 'blackwater' as mentioned in Stormwrack, which is 'deep water' that has negative planar gumph.

6 miles? You'd be just as dead if it was 300m, in reality, and if you were suddenly exposed to it without equalised air in your lungs: The internal voids in your body would be crushed to pulp. Although it [pressure] doesn't make it impossible to move, as the pressure is being applied equally.

That aside...
Frankly: Hand-wave it. And the bends. And Nitrogen narcosis. And Oxygen toxicity. And a dozen other physical effects that add nothing to the game. It's not worth getting into. We're talking about a game system where the skill of the swordsman (BAB) makes no difference in how hard it is to hit them, after all! Seeing as nobody is going to know in-game that not breathing out while swimming upwards with a lung-full of pressurised air is going to burst your lungs like a balloon, it's going to be a very dull game if real-world physics are applied.





In fact there is a sport based on this fact where you grab a rock, jump into the ocean, go down as far as you can and let go of the rock and swim like hell for the surface. Can't remember the name but they have beaten the depth records of people in scuba-suits because of this.

Free diving with weighted sledges (it's a little more sophisticated than using a rock). A cold and unpleasant way to die. Internal lung capacity is squeezed to about the volume of a baseball at extreme depth. coughing up blood afterwards is all part of the fun.

It certainly can't beat SCUBA kit as regards depth records, but it can beat depth records held for breathing compressed air. Reason being that the partial pressure of compressed air at depth is such that the Oxygen becomes toxic and causes seizures and death. Oxygen becomes toxic at around 1.6 Bar - or about 70m if breathing compressed air - making compressed air suicidal to breath at depth. Whereas a free diver is inhaling air at 1bar (and oxygen hence at 0.2bar partial pressure).

You can still get bent on a lung-full of air though, as pearl divers have historically suffered from it.

Sir Swindle89
2010-11-08, 01:06 PM
nitrogen in your blood will not be able to become liquid,

Not to be a stickler but i can't let you go on thinking thats how it works. Extra nitrogen goes into solution in your blood and then comes out of solution in the form of bubbles when the pressure is let off. Like opening the top on a soda bottle.

The warforged would be fine and be able to move around on the bottom reasonably well i suppose.

None of you would have to worry about depressurizing cuz you said you weren't that far from the surface.

Psyx
2010-11-09, 06:44 AM
None of you would have to worry about depressurizing cuz you said you weren't that far from the surface.

They're up to six miles from it! :smalltongue:

Greenish
2010-11-09, 06:49 AM
They're up to six miles from it! :smalltongue:"Mile" is just a fancy foreign way of saying "metre", right? :smalltongue:

Psyx
2010-11-09, 09:19 AM
Sure: centimetres and centimiles are interchangeable. So are fathoms and moles.

Sir Swindle89
2010-11-09, 11:03 AM
So the idea came up of just dispelling the magic holding up the room and swimming to the surface....because the DM said that the surface wasn't too far away. We were discussing the chances of drowning and other dangers to that when the one person chimed in; He's a Warforged, if anything happens he can just sink to the bottom and walk out.

Now we're in the middle of the ocean, Ignoring the likely possibility of him being eaten by a giant fish, we weren't told the depth, but since we don't know we can figure that it can be up to 6 miles, most likely less, but that's probably the worst-case scenario. So one of the guys says that if the pressure didn't crush you then it would be so strong that you wouldn't be able to move. His retort was that 'if we were using real world physics then mages' hands would be burnt and blistered from fire spells' So he hasn't read any rules on it, thus he feels that water pressure doesn't exist. That's my take on his response.

Close to the surface, possibly 6 miles from the bottom.

blackjack217
2010-11-09, 11:17 AM
"Mile" is just a fancy foreign way of saying "metre", right? :smalltongue:

no, no it is not. A mile is larger than a kilometer.

Psyx
2010-11-09, 11:25 AM
I think he was being ironic...

ShneekeyTheLost
2010-11-09, 02:06 PM
Sure: centimetres and centimiles are interchangeable. So are fathoms and moles.

I do believe that a Fathom is somewhat less than 6.02 * 10^23...

blackjack217
2010-11-09, 02:15 PM
is it not ironic to answer irony with irony?

Greenish
2010-11-09, 02:36 PM
I think he was being ironic...

is it not ironic to answer irony with irony?You keep using that word. I do not think it means what you think it means.

herrhauptmann
2010-11-09, 03:11 PM
Well the water bubble probably would equalize pressure for people inside, so they don't have problems due to pressure. You know, cuz it's magic.

Do warforged have blood? If the DM suddenly brings out a case of the bends, the easiest way for the warforged to avoid it? Take his time going to the surface. Seriously, he gets 100 ft from the surface, have him sit down for half an hour, it's not like he needs to breathe. Then he goes another 30 feet, and waits again. Unless the DM is working from a dive table, that's all the warforged would need (if they could get the bends).
Do warforged have sealed hollows within their bodies? Unless it's been explicitly stated, it's not like the pressure would cause his body to pop like an eggshell.
Even if your character could get the bends at that depth, it won't kill him. It'll just make you wish it had. The few people I've spoken with who experienced the bends, all made similar mistakes after a dive: Hot shower, and alcohol right after a dive.

For the rest of the party, what spells do you have available? And how good are your swim checks? I'd suggest the warriors stick their armor in a bag of holding beforehand if they don't have ranks in swim. How about being creative? Use the fly spell to control your movement in the water. Even if you end up slower than if you flew through the air, it would still be worth not removing your armor and shields.


Water pressure= Density of fluid times the height of the fluid above the point being measured.

Zeofar
2010-11-09, 03:31 PM
You keep using that word. I do not think it means what you think it means.

Irony: the use of words to convey a meaning that is the opposite of its literal meaning.

I imagine that you meant draw attention to the fact that miles are not equivalent to meters by feigning belief that they wouldn't have any depressurization issues because they were "only" six miles under, right? It also appears to me that the other person's use of irony was that they went along with pretending that you didn't actually know there was a difference between kilometers and miles; it is irony because he is actually agreeing with you while apparently disagreeing with you. As much as people on the internet love to go on about how "irony" only means "the opposite of what you expect," it really isn't true. Look up verbal irony, situational irony, and dramatic irony. It really is a versatile word.

Edit: Oh wait, did I just get ironized by Greenish? Dern kneejerk reactions.

Greenish
2010-11-09, 04:36 PM
Irony: the use of words to convey a meaning that is the opposite of its literal meaning.Huh. I always thought it meant "containing or having the qualities of iron".

As in, the 0th level ToB maneuver Irony Hit (for which the Steely Strike is an upgrade of).