Oops, I might of uh, made a small mistake.

[RainOfSteel]

How bad would it be if someone created two continuously connected portals, sent one into deep space, and dropped the other into the ocean?

How difficult would it be to do?
Do most of the realm worlds even have deep space?

I would say it depends on where in an ocean the source portal was dropped, in shallow water or in deep water, on a rocky bottom or mud, what kind of wildlife lived there, what kind of divinity or guardians were associated with the ocean, the portal's diameter, whether you consider the destination portal's structure to have a friction effect on the exiting ice, and we could go on and on.

Vibrations in the exiting ice column would, I think, cause it to break regularly. You would accumulate huge numbers of floating ice columns. They would exert very small gravitational fields on each other. After you had hundreds of thousands of them, you would have a giant mass of columns collected at the source portal, some floating free, some collected together in frozen palaces reminiscent of Superman's Fortress of Solitude. You could hypothesize that this would eventually plug the destination portal and stop any further drain and development.

Back at the source:

If the drain were going to affect the world seriously, the god of oceans/seas would take immediate interest. A giant rock slab, of the curiously unbreakable variety, could drop on the portal and shut it off. A hero could show up and disenchant it. Some desert dwellers learn of the destination portal, go and get it, and move it to their desert; water, water, everywhere!

The GM could decide that the immense pressure of water flowing through the portal created a destabilizing effect that eventually damaged the enchantment, that the immense weight of water at great depths crushed the portal into a twisted wreck, that a paragon whale got a little too close and became stuck in the portal, or anything.

 

[RUMBLETiGER]

How bad would it be if someone created two continuously connected portals, sent one into deep space, and dropped the other into the ocean?

That depends. If Water is considered an object by the DM in this case, than it would pass through on contact into space. If Water is considered an aspect of the environment (as air is on land) than there should be nothing happening until an object within the water touches the portal. Since Portals activate when a creature or object touches them, the void of space would not trigger the portals affect, there would be no vacuuming effect drawing anything into space, only whatever presses against the water side.

I'm assuming that when you say "Portal" you mean the kind described in Stronghold Builder's Guide and Forgotten Realms Campaign Setting.

If it is like a Ring Gate, than it'll pass 100lbs of water and/or objects a day, as long as they are within 100 miles of each other. If it is neither of these things, then it's something custom and there is no RAW to draw from to comment.

How difficult would it be to do?

If it is a classic portal, those are immovable. Therefore, the portal would have to be created as a 2 way portal from one of those two locations, and the creator must be familiar with the other side. So, you're looking at someone spending 100 days underwater crafting the portal, AND that creator is familiar with being in that section of deep space (or maybe a really quality Scrying). Sounds pretty hard to do.
If it's a Ring Gate, it's as hard as it takes to launch an object into space, and drop it to the bottom of the water. Once they move further than 100 miles from each other, they cease to function.

Do most of the realm worlds even have deep space?

Every Material Plane appears to have stars in the night sky, with the exception of Planescape to the best of my knowledge. If all of this is taking place in a Planescape setting, then it could be incredibly awesome and very plausible to create two portals like this.

Outside of Planescape, I really don't see this as very possible, according to any RAW I'm familiar with.

 

[Nimloth]

You could use a few decanters of endless water to offset the drainage. Or, even better, use a few decanters of endless rum and ever-so-slowly "transmute" the world's oceans into unsobering beverage. You'll be the stuff of legends among sailors and pirates!

Funny.

How bad would it be if someone created two continuously connected portals, sent one into deep space, and dropped the other into the ocean?

How difficult would it be to do?
Do most of the realm worlds even have deep space?

Umm, why do you ask?
>Looks stern<
a-d, what did you do?

 

[Tharkon]

Every Material Plane appears to have stars in the night sky, with the exception of Planescape to the best of my knowledge.

Those are painted on, silly.

 

[RUMBLETiGER]

I re-read the rules for Portals yesterday, they only allow creatures to pass through, not objects by themselves. A creature can bring objects through with them.

So, water will not flow through a Portal. That little Goldfish that was curious and swam to close? Bam, he's in space. Sux to be him.

 

[RainOfSteel]

If a GM say that there is a continuous portal, there is one.

I personally don't like the idea of a continuous portal-structure to portal-structure arrangement for exactly the reasons outlined in this topic.

I usually restrict continuous portals to a local geographical areas, one area in one plane, one area in another plane, that match up. People can walk through it if they know where the portal is, though they are often hidden and difficult to find. These arrangements do not cross oceans versus deep space or anything like that, so there is no matter transference due to some type of pressure imbalance. In special cases, multiple geographical locations could be involved in a single arrangement.

 

[Scott DeWar]

Rain of steel, that works quite well actually. In accordance with you equal environmental equilibrium, a portal between the depths of the ocean and the elemental plane of water is justified to pass said element of water.

 

[Tharkon]

Or there is an elemental guardian that brings the water trough the portal as a carried object as needed. This could even be the origin of how oceans came to be. Volcanos could be created by portals to the plane of fire and maybe the reason there is wind is because of air being added somewhere on the mountain peaks, and if it was not for earth being brought in from the plane of earth then it would just be a swirling mass of the other three elements.
Yeah, I think I'm gonna use this for my own campaign. Just have to find a solution for the fact by campaign is based on 12 elements, not 4.

 

[Scott DeWar]

12? quasi elements? I play in a game with 5 as per the chinese beliefs.

 

[Man in the Funny Hat]

1. Gravity in D&D (at least as defined by Spelljammer rules) is binary and monodirectional - that is, it is either on or off and all it does is pull things in one direction. It then might matter a great deal if one can enter either side of the portal or just one. If just one then it might matter which direction it's facing. Only if it's facing UP would water then be pulled into it by gravity. Otherwise, just because water is against the face/plane of effect of the teleportation doesn't give it the force needed to pass through.

2. Even if gravity works somewhat as it does in the real world and even if water would pass through the portal continuously it might still never drain an ocean. It would reach an equilibrium with the sphere of water it would be creating in space. The pressure of 1 atmosphere on your planet should eventually equal the gravitational pressure of the growing sphere of water in space - although I'm not sure where that would balance out.

3. One well-placed whale plugs the whole thing up by being physically unable to pass through the portal.