Castle Defenses

[robberbaron]

I'm with Tonguez on this. If someone wants an impregnable fortress you won't be able to see it or, at least, recognise it for what it is.

That said, castles are always popular with a certain class of 'nobility' and anyone who can afford to build one can certainly afford the magic to bolster its defences.
If it's in PHB then the defenders will most likely have thought of it. You have to be creative to succeed in a siege in fantasyland.

 

[charlesatan]

For the shrunken boulders, a permanent wind wall would do. Also discourages small flying creatures, small projectiles (arrows), etc.

You might also want to check out Stronghold Builder's Guidebook. It was released in 3.0 but some of the material there is easily adaptable (and has some tips). They also have stuff like walls with spell resistance for creatures on one side (preferably yours) and the like.

It also has some "modern day" items based on magic spells, such as dancing lights could be that tower spotlight used in prisons. It also has the metal obdurium which is twice as tough as adamantine, and magically reinforced materials (whether wood, stone, or what have you) which prove a low-cost method of strengthening the walls. Also has rules for earthquake and how it damages the structure.

 

[evilbob]

I got no problems with workarounds. What I want to see is:

Players: Attacking a castle is easy. I don't know why anyone builds them. We cast ABC.

Me (the DM): [checks notes] Turns out they thought of that long ago. Your magic ABC is met by magic XYZ and countered.

Players: *&%#!! Okay... give us a few minutes... [talk among themselves]. Now we try Plan B.

Me (the DM): [thinks for a moment] Yeah, that's clever and unusual. That'll work.

Um, actually... I wouldn't worry about it. The "turn into a tiny/invisible flying thing and drop shrunken boulders that will re-enlarge once dropped through the dispel magic field" is actually a REALLY GOOD PLAN. If your players somehow manage to come up with that on their own, I would reward their creativity, just like you said above!

 

[Pyrex]

The problem is that magical defenses are just too expensive to be practical. A permanent magical ward against attack N costs a 1000* or more the resources it does to attack with N in the first place.

The best way a king can spend his magical defense budget is to hire the highest-level party of adventurers he can afford and hope that they're at least as high level as the party of adventurers attacking his castle.

 

[HeavenShallBurn]

The best way a king can spend his magical defense budget is to hire the highest-level party of adventurers he can afford and hope that they're at least as high level as the party of adventurers attacking his castle.

Actually that may be the problem with assuming rulers are middling level characters, in D&D anyone powerful enough to protect your kingdom is powerful enough to usurp it, and most likely will. The ruler should be the single most powerful individual in the kingdom, if he wasn't someone else would have already done it and THEY would be king.

 

[Phaedrus]

Actually, I'd say the ruler has the support of the most powerful individuals. The super mage likely has no interest in the day-to-day drudgery of ruling. So he backs the king, helps as needed, in exchange for the freedom to do what he wants. Same for other uber characters.

 

[Pyrex]

Right, but either way those 'uber characters' or 'super mages' need to be in residence at the castle on a daily basis to fend off attacks.

It's not economically feasible for them to put down enough wards to protect the castle in their absence.

 

[Gerion of Mercadia]

Uh - why be in residence when you have Teleport without Error, or Gate, Or Plane shift?

 

[Quartz]

There's always Reverse Gravity.

 

[Jondor_Battlehammer]

A fantasy war is like a modern war.

People don't build castles anymore. They build bunkers.

True, castles should be built more like domes in high fantasy . Or just be a dwarf and don't worry about air assaults.

As far as a defense goes, build some cheap constructs that can fly, see invisible creatures, and would be a credible threat to small animals and flying wizards. They would fly CAP over the castle. Remember also they are in a three dimensional enviroment, use it to keep out of AoE.