Spells that Make Permanent Structures

So, according to the rules, a character can make a Wall of X spell that is permanent and undispellable. 

Would you allow this in your game? If so, how would you have it impact stronghold creation?

I'm using the Crimson Pandect and there is a 5th level spell that allows a caster to, over time, create large stone structures to spec that cannot be dispelled. My player wants to take that spell, but I am understandably hesitant, even though technically you could build something similar with the Wall Spell Creation rules.

What would you guys do?

In my version of the game, Wall of X can be permanent, but not undispellable. For undispellable things, you need Xform (i.e. Woodform, Stoneform, etc), which are ritual-level spells. The Xform spells (I believe) first appeared in Dawn of the Empires, and reappeared in the Rules Cyclopedia and in Champions of Mystara.

The pertinant part of the spell is this:

"he spell can
summon up to 500 cubic feet of rock per caster level
and can shape it into detailed forms at the caster’s
discretion. It takes time to fabricate these constructions,
requiring ten minutes for every 500 cubic feet of
rock to cast this spell."

Would you allow a spell that worked like that? If not, is it salvageable? 

I think my instinct would also be to confine permanent, nondispellable constructions to ritual magic as well.

Failing that, I would want the spell to expend GP based on its construction cost, making it a ‘fabrication’ spell instead of a ‘creation’ spell. I don’t think I’d want it to be possible to create strongholds with no weaknesses for free in significantly reduced time; if that were possible, it would change setting assumptions a lot.

I'd agree with Aryxymaraki. 

There's enough math popping around that it should be pretty elementary to take the various construction costs and rules and turn that into a ritual spell that summons a horde of 'unseen laborers', that, given a pile of raw materials or buildings to scavenge, pops a tower up in a eldritch way.

Aside, perhaps, from being really flumphing impressive to the neighbors, the ritual spell's "unseen laborers" are immune to the reduction of efficiency from the maximum workers rule - so the mage can overload the construction site, as the unseen laborers are perfectly choreographed by the magic of the ritual.

Haven't done the math on that, but under the general rule it's a 50% return, where this would be a 100% return on extra labor costs sunk after the first 3,000 laborers  (I think, it's early still)


The cheapest, permanent, non-dispel-able wall is as follows:

Impermeable to creatures. Impermeable to vision and light (opaque). Not affected by disintegrate. Area may be crudely shaped by reducing area. Wall must be bonded to surrounding material. Wall must be solidly supported. Wall must always be a flat, vertical plane. Wall must always be in contact with ground. 0'. Indefinite (until dispelled/destroyed). 500 square feet. 10' thick. May not be evoked where objects/creatures are. No saving throw permitted. Arcane. Total: 42.42, Spell Level 5

That is a 50' tall, 10' thick, 10' long wall that can't be used as floor or ceiling, and can only be crudely shaped. Ceilings, floors, crenellations, even windows require a different spell (same, except 1' thick, readily shape-able, and not to be a vertical plane). Anything fancier, and it's going to be a 6th level spell or more. If you were to hire a mage to cast the spell(s), it would cost 1,250gp per cast; a 100' long wall, therefore, would cost 12,500gp. The equivalent (non-disintegration-proof) mundane wall would be 17,500gp. So, you see a savings of quite a bit of time (10 days instead of 35), and 5,000gp. It's not such a bad deal, as long as you're building flat, square, magically fortified walls, and have access to a Class IV market or better. However, I personally would rule that such a wall is smooth and strange; impossible to build on top of, since there's no way to dig into it, and obviously magical. Anything connected to the wall must be magical, since this material is nigh-on indestructible, or else the non-magical part (say, a gate) must exist before the wall is added. While the wall itself will save you money, a 10gp arrow slit is going to cost 1,250gp; a 200gp, 500 square foot floor is going to cost 1,250gp. A basic flight of stairs is going to cost 3,750gp (three 1'-wide casts) instead of 60gp!

Moving parts like doors, shutters, etc. are impossible, which means any egress points will have to be in place before hand, and made of mundane materials, which are much, much weaker than the surrounding structure. Otherwise, the pieces will have to be built in advance, hoisted into place, and attached. Repairing such a point will be very expensive. And of course, you'll still have to pay for an engineer to design the layout and instruct the caster(s) on where to place the walls. Stronghold upkeep should still apply, using the cost of the spells as the base cost.

That said, magical walls make sense, as long as it's a basic, featureless wall, but anything more than that is going to be hugely expensive. Worse, planning will have to be perfect; there is no way to demolish part of a wall and expand. You have to either build in "connection" pieces that aren't permanent, and are thus weaker, or just abandon your old buildings entirely. Still, all in all, it sounds like magical constructions are cheaper and faster than normal construction, and much more durable...

Except they aren't!

A Rod of Cancelation costs far less than the army required to storm a mundane castle. Permanent and non-dispel-able they may be, but the walls are still magical. With a touch, the wall, the castle, the floors and ceilings and steps and everything else turn into a mundane version - and, in this case, since the walls are purely magical, the mundane version is "nothing at all".