Building a fortress.

[Shinizak]

So I've got this idea of a large castle, or head quarters. Maybe like a thieves guild. What I want is mundane methods of keeping out magic (or other attacks/tricks), the thieves guild has a strict policy on no magic within the guild (since the last thing a thieves guild wants is it's members throwing around illusions and divination abilities). Basically, we're looking for "alarms" that can't be deactivated.

I've already got a few methods for keeping out a few spells:

Floor made of sand: Every room and hallway in the building is made up of or covered in a 3-4 foot layer of fine sand, making it easy to detect foot prints of invisible foes.

Curtains in the hallways/doorways: For if anyone attempts a fly+invisibility combo, they'll still have to fly through the curtains and cause unusual motions in the fabric. As a plus you could also have the curtains be made of a see through fabric, thus allowing guards to still do their job.

Torture chamber: Ethereal invaders are a major problem, during darker times the thieves guild took to torturing people to death in an effort to create malevolent ghosts. They did this as a way to at least have an indirect method of combating ethereal travelers.

If you have any more feel free to share.

[Darcand]

Why not have the whole building permanently Silenced? And the members only communicate through Thieves Cant....

[Shinizak]

Why not have the whole building permanently Silenced? And the members only communicate through Thieves Cant....

Because the thieves don't want to have ANYTHING to do with magic.

[Choco]

Well, if they are a powerful enough guild I am sure they could "acquire" some sort of item that projects a permanent AMF that encompasses the whole castle.

Though that depends on if they view magic-cancellation items as being magical

[Shinizak]

It's not a question of what is practical, it's a question of how they want to go about it. The thieves guild can use magic, they just flat out don't want to.

[Elfin]

I'd say no to the sand floors; it'd be inconvenient to always have to tread around in sand, and think of the mess.
Reinforce the walls with adamantine for strength, and a sheet of lead to prevent x-ray vision. Make sure there are no parapets or places where a flying spellcaster could land. Don't give the guards the ability to open the gates; otherwise they could be easily charmed. Instead, have a bell that the gate guards ring if it's safe to open the gates, and hearing the bell will let someone in a higher, separate and windowless room (with the power to open the gate) know they can open up.

This focuses more on keeping spellcasters out; inside, the ghosts and curtains are a good idea.

Ghosts especially for etherealness; teleportation is still a problem though.
And without a ward for scrying, it'll be easy to bypass all of the protections.
Frankly, you're never going to be able to keep out a wizard or sorcerer without using magic.

[Shinizak]

I'm going to use magic where I ABSOLUTELY must, but before that I'd like to exhaust my mundane options.

[Sstoopidtallkid]

All walls and floors need to be at least 6' deep(to prevent most incorporeal travel). This also blocks the majority of divinations from the outside. For preventing casting inside, I can't help you, though maybe filling the corridors with a bit of fog would reveal invisibility/illusions...

[Kzickas]

there's a spell in sandstorm that allows you to turn into animated sand, so the sand on the floor trick should be avoided

[Shinizak]

Okay, then how about a layer of water on the floor in the hall ways?

[Darkmatter]

Depending on how established your campaign world is, DM fiat is your friend here. In my campaign world, the range of magical effects is blocked by a good deal of earth, a foot of stone, an inch or so of most metals, or a thin mesh (think chicken wire) of lead. Magic can affect these materials, but the range of any spell ends at such a barrier. This allows the nonmagical construction of fortresses that are resistant to divinations and teleportation from the outside by using (for example) thin, lead coated chains draped over each of the entrances to an underground dungeon.

Another detection option is covering the walls with steady sources of flame that will move if anyone passes. I do like the sand idea. A semi-practical improvement to prevent sand from getting everywhere would involve a transparent membrane covering an evenly distributed and visible substance. Pressure would displace the substance, allowing the location of the pressure to be observed. This could be achieved nowadays with plastic and a dyed synthetic gel - in ancient times, small glass plates or layered animal gut over connected and lightly pressurized chambers of dyed water or ink might work. Nightingale floors are another (and actually used) approach to a similar end.

[awa]

pet brain moles could help disrupt psionics, make lots of secret door and line every thing with lead.

[Croverus]

Whata botu having "guard animals" that have some abilities that could count as magic? Cause if you'll allow that, Manticores, Gargoyles and Constructs are all very useful for guarding a castle.

[herrhauptmann]

Stealing from the movie 'Antitrust'
The rich man's mansion has sensors built into the walls that detect a person by their biochemical signature or somesuch. And they detect not just when a person has entered a room, but who has entered teh room.
They then alert other people by flashing lights on the wall in a pattern, and playing theme music. So you know who's entered without looking at the door.

I think one shot visitors to the mansion got a generic pattern and music (probably included thieves).

It's a thieves guild, so the presence of bards and illusionists doesn't seem too far-fetched. And it could be a neat little bit of flavor text and munchkinery to throw in.

[KillianHawkeye]

Stealing from the movie 'Antitrust'
The rich man's mansion has sensors built into the walls that detect a person by their biochemical signature or somesuch. And they detect not just when a person has entered a room, but who has entered teh room.
They then alert other people by flashing lights on the wall in a pattern, and playing theme music. So you know who's entered without looking at the door.

I think one shot visitors to the mansion got a generic pattern and music (probably included thieves).

It's a thieves guild, so the presence of bards and illusionists doesn't seem too far-fetched. And it could be a neat little bit of flavor text and munchkinery to throw in.

Did you read this thread at all? It's a thieves' guild that abhors ALL magic! I seriously doubt they'll have bards and illusionists on hand.

I would say the best bet for mundane defense is for the actual guild to be underneath the keep in a lead-lined dungeon. The most important thing here is secrecy. The wizards can't teleport in if they don't know the layout, and they can't scry inside if they don't know who's part of the guild. There should be secret tunnels connecting the guild to various hidden exits and entrances a good distance from the keep. The only people who should actually enter and leave the building from the surface entrance should be those who never take the secret doors to the actual guild halls (i.e. decoys). It could be even better if there isn't even a way to get from the keep to the dungeon below at all. That makes the entire keep into a decoy.

[herrhauptmann]

Yes I read the thread.
Where possible they use nonmagical things.

Where necessary, they use magic effects.

And it's not that they abhor all magic. They just don't want people casting within the guild house.

[Lamech]

If your in deep shadow you arn't connected to the astral plane and porting in becomes impossible. You can still wish or gate (I think) your way in but those are kind of hard to stop anyway.

You could also as the DM fiat that the thieves guild built it in a place not connected to the astral plane.

[awa]

while certainly not even remotely practical you could capture a bunch of beholders cut off their eye stalks and chain them to the walls covering the inside of the building in an anti magic field

on a more practical note being ridiculously secretive seems like the best option and for a thieves guild that makes lots of sense. putting it underground like say in one of those giant fantasy sewers would be a great idea makes hiding it easier the stone should be thick enough to block most divination the water on the floor reveals invisible beings.

[The Gilded Duke]

Get some guard dogs. Have them bark whenever they pick up someone unfamiliar with scent. Should be able to detect all but superior invisibility. Also if you want to include some monsters hire some Grimlock guards to use their 60 foot blindsight to pinpoint where intruders are.

Greater Teleport you can't do much against, but regular teleport you can increase the chance for mishaps pretty easily. Just alter the inside arrangement of rooms every week or so, move around some furniture, rehang some curtains, break down or build a few new walls. Thus making a "familiar destination" completely altered to qualify as a "false destination"

Have a similar looking building set up nearby for porters to get shoved to. Make there be some hazard, maybe fill it with monsters, or make it underwater or otherwise have no air.

Not sure what to do about scryers though.

[shadow_archmagi]

Get some guard dogs. Have them bark whenever they pick up someone unfamiliar with scent. Should be able to detect all but superior invisibility. Also if you want to include some monsters hire some Grimlock guards to use their 60 foot blindsight to pinpoint where intruders are.

Greater Teleport you can't do much against, but regular teleport you can increase the chance for mishaps pretty easily. Just alter the inside arrangement of rooms every week or so, move around some furniture, rehang some curtains, break down or build a few new walls. Thus making a "familiar destination" completely altered to qualify as a "false destination"

Have a similar looking building set up nearby for porters to get shoved to. Make there be some hazard, maybe fill it with monsters, or make it underwater or otherwise have no air.

Not sure what to do about scryers though.

Elaborate clockwork system to keep everything moving constantly. A sort of gnome-engineered version of Hogwarts.

[Mando Knight]

Torture chamber: Ethereal invaders are a major problem, during darker times the thieves guild took to torturing people to death in an effort to create malevolent ghosts. They did this as a way to at least have an indirect method of combating ethereal travelers.

Why would the malevolent ghosts attack the intruders, and not the members of the same thieves' guild that tortured and killed their original selves?

[BobVosh]

Build on a dead magic zone?

Make a cloth that exists on the astral plane as part of its creation process. Some mumble jumble about being weaved in a spiritually rich location. Make tapestries, hanging drapes, and lay it on the floors beneath the sand.

Any creatures that can detect magic naturally?

Maybe put rods of wonders around, if that doesn't offend em.

[Myiven]

Considering that it's for a thieves guild, how about a much more subtle approach? Instead of a permanent structure, they could have a system of moving safe houses, hand picked by the guild leader who then notifies the other members with highly encrypted mathematical cyphers.

The individual safe houses would only be used for a few hours at a time, making scrying almost impossibly frustrating and fruitless, especially if they also write and speak in cypher. Since cyphers are technically algorithms and not languages, magical abilities to comprehend languages shouldn't work.

By scattering their membership between meetings, and having a random number of members not move to the next safe house would make more mundane methods of tracking and infiltrating difficult.


Of course now they're sounding more like accountants than thieves with all of these cyphers and random systems. Heh. I got carried away there.
Since you have a strictly no-magic systems, I tried to think outside the box. Most anti-magic requires a magic of some sort.

Good luck!

[Hawriel]

I honestly cant see why a thieves guild would want to build a big fort. I can not fathom why this thieves guild would refuse to use magic in an obviosly high magic world. This thieves guild has, by the OP's examples, has a very good idea what magic is capable of. What you describe suggests a high magic world. Refusing to use magic would cripple the guild's ability to funtion in this world. IF this is so important to the guild mabe you should come up with a very deep motivation for the guild to refuse to use magic. Somthing alot more believable than 'they dont want to'.

[Fixer]

while certainly not even remotely practical you could capture a bunch of beholders cut off their eye stalks and chain them to the walls covering the inside of the building in an anti magic field.

If this thieves' guild is anti-magic, keeping a couple beholders chained up (and keeping their non-anti-magic-ray eyes 'trimmed' regularly) and their eyes focused on the entrances to the 'fort' would be within the description.

I don't think there are established items that do what you describe you wish. You will likely have to go outside the established.

Try saying that the thieves located an unusual vein of stone that runs through a series of underground caverns under an old fort (made of the same stone). This stone causes all ranged spells (spells with a range other than 0 or personal) to be redirected INTO the vein (and thus fail) causing the stone to brighten and give off light based on the caster level to a radius based on the spell level. Attempts at mining this stone and moving to other locations has been impossible as it seems to be something about the location (this prevents too much player abuse). Some other aspects of this material are that it exists in both the ethereal and the prime, so attempts at passing through the location ethereally fail due to the latticework of stone everywhere. Have the doors made out of the same type of stone for the same reason. Given it is highly disruptive to magic, anyone scrying gets static (it isn't prevented from working, just too much static to see/hear anything) and anyone attempting to teleport into it (or out of it) takes damage.

Non-magical solution to a magical problem that the players cannot 'steal' to use themselves, unless they want a base of their own.

[Irreverent Fool]

Don't see why you'd need sand. Doors work fine.

A good thief will know how to cover his tracks or otherwise avoid the sand. Of course if he's a thief, why's he sneaking around in the thieves' guild? and if he's not a thief then it's probably a bad idea to try to sneak around the thieves' guild.

So, the topic is 'mundane security to best a magical opponent'. If the thieves are unwilling to use magic but willing to have ghosts guarding their base, I don't know what you're looking for. I think the best thing (as a DM) to do would be to have the entire place based around a powerful anti-magical artifact that shrouds the entire complex in antimagic and nondetection along with deadly, deadly traps and confusing mazes.

Edit: Or the above. I missed the 'antimagic vein' idea somehow.

Unless there's a specific 'level' of magic you are trying to protect against, no mundane method will work.

obnoxious
sig

[Fixer]

Edit: Or the above. I missed the 'antimagic vein' idea somehow.

I think I am made of a vein of flesh that contains an "ignore this poster" field. As a result, my posts are often overlooked the first time. ;)

[bosssmiley]

I think I am made of a vein of flesh that contains an "ignore this poster" field. As a result, my posts are often overlooked the first time. ;)

Someone say something?

Denying caster types access to your sanctum, some old school methods:

• lead in the mortar and window frames (lead blocked line of effect for teleporting and astral projection)
• a layer of ivy on the building (living material also blocked line of effect)
• distributed/non-intuitive internal layout (teleporters get caught in the walls)
• teleport traps (vats of acid/burning oil at expected ground zeroes)

Unfortunately OP in WOTC D&D you're dealing with a game where magic largely - and generally without exception - trumps non-magic to an extent that isn't even funny. Caster fap in 3E is such a bad joke that WOTC broke the game in the other direction by trying to fix the problem with 4E.

Power blocs in D&D-land either:

1. exploit magic to the hilt,
2. exclusively prey on the weak and low level, or
3. get trampled on by the first full caster-supported crew they cross

Ignoring magic in D&D is like ignoring guns in modern warfare: self-destructive and stupid to the point of suicide.

[Shinizak]

I do realizes that it's hard to trump magic, that's why I'm doing this. The thieves guild simply believes that they shouldn't have fancy magic protections in their home (which can be deactivated with a disable device check) while forcing their members into a fortress with a "no casting" policy. Thus, they talk use the power of the average folk to beat a wizard...

[aivanther]

Tanglefoot bags can be helpful at low levels...set up several traps with them.

You could also try and come up with an alchemical equivalent of a flashbang: blind and deafen them.

Set up the guild house in a dead magic zone? I believe they would be technically "natural".

Psionics?

Are they just against arcane? If so, would divine casters be useable?