Floating Castle

[Ponce]

Here's the deal: Make a castle that can be held up by immovable rods.

I've tried it numerous times, but every time I'm knocked back by the sheer tonnage of the thing. Assume we have an outer wall that is 7 feet thick, 30 feet high, and, we'll say, 400 feet long (a rather modest castle).

That amounts to 84,000 cubic feet of lime stone.

Lime stone weighs around 165 pounds per cubic foot.

So this wall is around 14 million pounds, or 14 thousand tonnes.

Thus it would require over two thousand immovable rods to hold up! Fairly infeasible. And that's just the curtain wall.

I've tried a number of things, like using other materials, casting hardness to reduce the necessary thickness, different dimensions, but the amount of rods required is completely infeasible by WBL.

Help! How can this be made to happen? Is there a Greater Immovable Rod somewhere? A way to keep the structural and defensive strength while significantly reducing weight (Hardening, for example)? Something?!

Stipulations:
-Stay in WBL. No loops or tricks to get extra cash. Landlord shouldn't apply to the cost of the rods.
-Artificer is preferred as the class, for cheaper access to the rods. Probably around level 12.
-The castle should be just that, a castle, but it can be made of anything that can resist siege and hold itself up at least as well as normal castle materials (limestone).

[AgentPaper]

Alternate solution: Pick up the Stronghold Builders Guide, which has rules for floating castles, including costs, among other things. You can even make the thing move around if you want, though that's a bit more expensive.

[Myrmex]

If you're stuck inside of core, use animate object + permanency & mass fly. It'd take a lot of castings, but it'd be possible.

A single colossal animated object can carry 19,200 lbs. So you need 730 of 'em to carry your castle.

[Lysander]

Immovable rods are for suckers. Support the castle with a few well placed permanent Walls of Force inside the masonry. They can hold INFINITE weight. All that matters is having a clever architect who uses them as big rectangular support pillars for the rest of the structure.

[Myrmex]

Immovable rods are for suckers. Support the castle with a few well placed permanent Walls of Force inside the masonry. They can hold INFINITE weight. All that matters is having a clever architect who uses them as big rectangular support pillars for the rest of the structure.

I just realized he wanted a floating castle, not one that could fly.
Permanent Walls of Force are definitely the way to go.

[Alex112524]

I just realized he wanted a floating castle, not one that could fly.
Permanent Walls of Force are definitely the way to go.

Just make sure to put them behind thick walls of something that would prevent them from being dispelled

[Tackyhillbillu]

Build the Castle out of Lead.

[sambo.]

Just make sure to put them behind thick walls of something that would prevent them from being dispelled

Wall Of Force cannot be dispelled

however, it can be Disintegrated

pray someone doesn't Disintegrate one of your pillars, turning your expensive floating castle into so much rubble.

how about some kind of oversized Tensers Floating Disk to build said castle upon? or judicious use of Reverse Gravity?

[Akal Saris]

I wish I could help, but I don't know of any source that has a greater immovable rod, and most materials don't list an accurate weight, so it's tough to figure out the weight of materials. I definitely think it's possible with something like a mithril tower though.

And yes, wall of force or the SBG's hovering enchantments work well too, as would the Skycastle spell from...Dragonlance maybe?

[Ponce]

Alternate solution: Pick up the Stronghold Builders Guide, which has rules for floating castles, including costs, among other things. You can even make the thing move around if you want, though that's a bit more expensive.

Yeah, I know, but at 15,000gp/SS its incredibly costly with no real way to optimize. Plus, as noted above, the goal is to try to get a floating foundation on which to build something.

The walls of force seem like a good option, though! Just need to find a way to keep the permanency from being dispelled. Keeping the wall of force 20ft from any exterior should be a good start, but are there any other fail-safes one can put in place? This would certainly eliminate the need for rods altogether, and is damned cheap. I mean once the wall of force is in place, you can just make a giant, flat, wall of iron to rest atop it. Then build the castle on that.

[Johel]

Ok, here's the deal, then :

Wall

• 7 feet thick
• 30 feet high
• 400 feet long
• 165 pounds per cubic foot
• 7 x 30 x 400 = 84.000 cubic feet
• 13.860.000 pounds per wall.

A reverse gravity trap allows you to affect the surrounding a minimum of 13 cubes, each 10 feet large. That's at least 13.000 cubic feet at CL 13.
Each trap will cover a area 10 ft thick, 40 ft high, 30 ft long, with the last cube being used to work out minor feature.
14 of them can cover the whole surface of the wall.

1 trap costs 500 x 13 x 7 = 45.500 po
14 of them cost 637.000 po

Now, all we need is to set them on the wall (which must be unattached to the ground) and activate.
Round 1, 1st activation.
The whole structure will rise 10 ft above the ground in round 1.
Round 2, 2nd activation.
The whole structure will rise 20 ft above the ground in round 2.
Round 3, 3rd activation...

Now, it's not flying but it's floating, right ?

[Lysander]

The walls of force seem like a good option, though! Just need to find a way to keep the permanency from being dispelled. Keeping the wall of force 20ft from any exterior should be a good start, but are there any other fail-safes one can put in place? This would certainly eliminate the need for rods altogether, and is damned cheap. I mean once the wall of force is in place, you can just make a giant, flat, wall of iron to rest atop it. Then build the castle on that.

You'd probably want multiple Walls of Force spread throughout the castle to act as redundancies, so no one Wall is crucial to support the whole thing.

You could build the castle out of layers of different materials so no one spell can quickly bore a hole into it. Have an outer layer of stone, followed by a layer of steel, etc. so Soften Earth and Stone and Rust would each have to be cast multiple times to make any progress.

Sandwich each wall of force between layers of Ironwood. That way if your enemy can get through all the surrounding stone and metal they also need a way of destroying steel-strong wood to even get a glimpse of the Wall of Force.

Draw of Symbol of Fear on each Wall of Force so that when someone finally uncovers it instead of casting disintegrate they instead flee in terror.

Make it hard for fliers to approach your castle. Have arrow slits not only on the sides but on the bottom so archers can shoot and pour hot oil on things below.

Have flying and wall crawling units as sentries.

Use permanent image to create all sorts of illusory towers, doorways, windows, etc. so an intruder will have trouble figuring which entrance is real.

Here's a novel idea: prepare for the worst. Design your castle in connected segments so that if the Walls of Force in one part are destroyed, only that part falls and the rest remains aloft. That way you can rebuild any destroyed segments instead of losing the whole castle.

And very very important, make sure every non-caster in your party has a Ring of Feather Falling.

[bosssmiley]

So this wall is around 14 million pounds, or 14 thousand tonnes.

2,200lb = 1 ton. So that's about 6,360 tons.

Thus it would require over two thousand immovable rods to hold up! Fairly infeasible. And that's just the curtain wall.

A curtain wall on a flying castle? Someone ain't thinking.

Just steal (and adapt to your smaller scale) a Cloud Giant cloud castle. Job done. The DM does not BIG BAD "I SAID NO!" such an idea as it is a delicious adventure hook with the potential for an entire campaign: "Adventures in the Lands Beyond the Clouds". In what way is the exploration, invasion and conquest of the kingdoms of the air not the stuff of high-level D&D adventure.

How do you catch a cloud castle? Beanstalks + plant growth are traditional, but I understand huge hooks + mountaintops, or galleons lifted by hot air balloon and flight of griffons work too. Teleport you say. Where's the fun in that?

[jiriku]

Hire a red wizard circle to cast the spells for you. When those walls of force are cast at CL 40, they'll be quite difficult to dispel.

[Radar]

To prevent your Walls of Force from being desintegrated, cover them in permanent Antimagic Fields! It will block most spells, but the walls will be intact.

[Another_Poet]

The real probpem isn't the weight, as I assume you can find spells and special materials to get around that.

The real problem is the structural integrity - the castle wall is more likely to crumble and fall, leaving the immovable rods hanging in the sky with a couple bricks on top of each.

If you're a player and you don't have the Stronghold Builder's Guide, ask your DM if you can invent a transumtation spell to reduce the weight of the stone. The hire someone with a very high Knowledge (Architecture & Engineering) to design the walls to carry the weight to the rods. Expect to need some metal trusses to do the actual weight-bearing, with the stonework being merely decorative.

If you're the DM, don't bother with any of the above. Just put a floating castle there and say it's held up by immovable rods. If you have a player who knows enough about engineering to complain, let him/her come up with the explanation of how it was done.

ap