Help Me Build A Castle That Can't Be Beat (Unless You're A Commoner)

[Kyouhen]

Greetings!

So in the campaign setting I've got there's this massive evil castle of evil in the middle of a city. The guy who lived in the castle ruled the plane with an iron fist, but has long since been disposed of. The people in the city know that the fortress is a big deal, and it's relatively easy to get to (all you need to do is fly up to where it is.)

Now here's where things get tricky. This city is full of adventurers, a few dozen of which are above level 15. The castle is clearly going to have awesome loot in it. But nobody goes up to it because nobody who's attempted to raid the castle has come back alive. It's a touch essential that nobody that leaves is heard from again on the grounds of making sure nobody can leave and tell the rest of the adventurers how to get past some of the defenses, increasing the odds of going further. It should be noted that the PCs are never to go to this castle. Visiting it is a death sentence, which should be obvious by the fact that the NPCs that are level 18-20 won't even go in there. The PCs /can/ visit it but I have no issues killing them if they do (after sufficient "Are you sure?"s are thrown their way)

Now the big guy in the castle didn't like relying on creatures and soldiers to defend his castle. There's a few gods that kind of had it out for him, and he'd rather not let his secrets fall into the hands of divine beings long after his critters have died off. And intelligent creatures have an annoying habit of being reasoned with. Can't have that. So he strongly favours various forms of traps. He also had an army of slaves, and didn't trust them with any form of knowledge of his defenses. So what he'd do is build traps that increase in effectiveness based on how strong the person entering the castle is. His level 1 commoner slaves are free to move through the castle as they please as they simply don't have whatever is needed to trigger the traps. A low level adventurer might be bothered by some of the traps but likewise aren't going to feel the full wrath of the castle. A high-level god-slaying adventurer capable of being a serious threat to the big guy, on the other hand, will only get through one or two rooms before dying horribly. (Yes, the PCs will be able to get their hands on an absurd amount of valuables if they make the stupid decision to visit the castle super early. Just because I'd love to see the discussion that leads to them deciding to visit the castle where every high level adventurer vanished at level 3. :smalltongue:)

So far I've only really come up with two rooms:

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Sacrificial Gate
Not sure if I'd actually use this one. The idea is that there's a stupidly heavy door leading into the next room (maybe a treasury or something) There's a set of chains with manacles going into holes in ceiling and floor, and a big old lever. If the players pull the lever the chains in the ceiling will get pulled up until the manacles touch it, then there'll be a loud click and the chain will promptly fall back down.

The trick is that to open the gate someone needs to be strapped into the manacles. The manacles themselves are antimagic manacles, so summoned monsters will immediately poof away and you won't be able to teleport out of them. Whoever's strapped in needs to make multiple Con saves to not be ripped in half, getting more difficult the more rounds the door is kept open. Someone will need to unstrap the guy, but that'll result in the door slamming shut on both of them. When one manacle is released the saves will get harder but the result will be limb loss instead of death.

The real catch? This mechanism is on both sides of the door, and the door and walls are thick enough you can't communicate through them. (Probably enchanted to prevent magical communication into those rooms as well) So one person is going to end up trapped on the other side if they want to let the rest of the party get back, and that assumes enough people went through the door to even open it from the other side.

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The Castle Hall
Now this one I like. The party enters a large hallway with a door on the opposite end. (We're talking 200 feet or so) Once the party is about halfway into the hall, the trap triggers and the doors at either end slam shut (if they were left open.)

Now my group likes to keep a kill count of everything they've killed. It's an amusing little contest for them. So I keep track of everything they've ever fought and who delivered the killing blow. I compile this into a massive chart. Every round (maybe less, would have to look at it at some point to see how tough it is) I roll on the list of past encounters. The hall summons all the monsters the players killed during that encounter, and each player that made a kill during that encounter loses the XP they got from it. Each creature summoned can only harm and be harmed by the person that originally killed it. When the player that made the kill has beaten everything they killed in that encounter they regain any lost XP. The big panic trick and the way commoners are immune to this? The doors are magically sealed against anyone trying to fight one of the summoned monsters. The only way to open the door is to kill all of your enemies, but the longer that takes the more will show up. (Also it'll be particularly unpleasant for the poor rogue that got the killing blow on that dragon a few levels back) Good news is the doors only close on their own when the trap is first triggered, so the party support who's never killed anything in his life can just walk over and open the door and let everyone else out. Note that you only get the lost XP back when you kill the creature that was summoned, fleeing the room won't give it back. Once you've left the room any creatures summoned by your presence vanish, and when the entire party leaves the trap turns off until they enter again.

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So, looking for any help. Can anyone else come up with any horrible things to throw at any adventurers that decide to wander in here? Remember that killing them is entirely the point, but it has to be (relatively) fair and something that someone with zero experience can simply walk past without a problem.

[Arcangel4774]

I imagine a commoner walks through your second trap and after a while gets eaten by the accumulation of all the mosquitos has killed throughout his life

[Unoriginal]

So, looking for any help. Can anyone else come up with any horrible things to throw at any adventurers that decide to wander in here? Remember that killing them is entirely the point, but it has to be (relatively) fair and something that someone with zero experience can simply walk past without a problem.

There is a magic detector in a room. If it detects anything magical, 500 kg metal gates drop at both entrances of the room before locking into place, trapping the characters hermetically. It is impossible to teleport out of the room, or use magic to go to another dimension/go through the walls/etc.

The doors won't open until everyone in the room is dead.

[Nifft]

I imagine a commoner walks through your second trap and after a while gets eaten by the accumulation of all the mosquitos has killed throughout his life

Alternately, the Commoner was a farmer, so every few seconds a chicken appears somewhere on the commoner's body.

This magical trap is a mechanical explanation for the 3.5e "Chicken Infested" flaw.

[Kyouhen]

I imagine a commoner walks through your second trap and after a while gets eaten by the accumulation of all the mosquitos has killed throughout his life

Amusing, though technically the trap can only create enemies that grant XP. (Though it would be amusing to keep summoning rat swarms the wizard decided to nuke ages ago)


There is a magic detector in a room. If it detects anything magical, 500 kg metal gates drop at both entrances of the room before locking into place, trapping the characters hermetically. It is impossible to teleport out of the room, or use magic to go to another dimension/go through the walls/etc.

The doors won't open until everyone in the room is dead.

Tempting but it would prevent Evil Dude from transporting any magical objects through there.


Alternately, the Commoner was a farmer, so every few seconds a chicken appears somewhere on the commoner's body.

This magical trap is a mechanical explanation for the 3.5e "Chicken Infested" flaw.

Ooooohhhh I like this idea. Note to self: Work that in there somewhere.

[Hrugner]

You could always go with an anti-magic moat. The castle proper is in another plane but poking through into this plane via a massive permanent gate. The castle isn't large enough to completely fill in the gate, so there's a large gate moat around the castle. The gate powers itself by absorbing ambient magic and pulls nearby spells, enchantments, and spell casters into the gate if they get close. Should anyone reach the castle they are affected by the laws of the plane from which the castle originates. Time passes very quickly in this other plane, so anyone going through at a slow enough pace is unnaturally aged in sections with their front crumbling to dust before they can completely enter.

[Kyouhen]

You could always go with an anti-magic moat. The castle proper is in another plane but poking through into this plane via a massive permanent gate. The castle isn't large enough to completely fill in the gate, so there's a large gate moat around the castle. The gate powers itself by absorbing ambient magic and pulls nearby spells, enchantments, and spell casters into the gate if they get close. Should anyone reach the castle they are affected by the laws of the plane from which the castle originates. Time passes very quickly in this other plane, so anyone going through at a slow enough pace is unnaturally aged in sections with their front crumbling to dust before they can completely enter.

Hmmm... The castle is technically on top of a massive pillar of stone, but I kind of like this idea. The top of the pillar was just hacked off via the gate with the castle sticking out the top. The castle fills enough that anyone flying up to look from a distance wouldn't notice anything, but if you get too close it sucks you in. I could work with this.

[MadBear]

Hall Of Just Rewards

This magical chamber measures the worth of any character that enters. For those that are truly just, and have spent their life serving others, the hall creates the illusion of their biggest fantasy coming true. The PC imagines spending the rest of their life happy and fulfilled. In reality, the PC is left standing their slowing dying of dehydration, lack of food, and lack of sleep. Eventually their body shuts down, killing them without them ever knowing what actually happened. (anyone who tries to enter the room to save their friends suffer the same fate). If someone was to view the room without the enchantment it'd be piled high with the bones of adventurers who never made it past this first trap.

[polymphus]

Re the commoners getting in, if they're slaves it's fairly easy -- the boss has given them a magical brand that has horrifying negative effects on them but also lets them pass through the traps safely.

Your players won't want the brand (make it something ridiculous like "INT and CHA are reduced to 1, affected loses the ability to speak, cannot be removed even with a Wish spell") but it explains how everybody is getting in and out.

[Dappershire]

You could always go with an anti-magic moat. The castle proper is in another plane but poking through into this plane via a massive permanent gate. The castle isn't large enough to completely fill in the gate, so there's a large gate moat around the castle. The gate powers itself by absorbing ambient magic and pulls nearby spells, enchantments, and spell casters into the gate if they get close. Should anyone reach the castle they are affected by the laws of the plane from which the castle originates. Time passes very quickly in this other plane, so anyone going through at a slow enough pace is unnaturally aged in sections with their front crumbling to dust before they can completely enter.


I was coming to say this. If it takes flight to enter the castle grounds, then have the castle itself be an image, coming in from another realm via giant portal.

That realm? Ravenloft. Nobody ever comes back from Ravenloft. Hos are all about the sexy undead.

If your players dare try for loot? Boom. Stuck in Werewolfville. Countotopia.

[Kyouhen]

Hall Of Just Rewards

This magical chamber measures the worth of any character that enters. For those that are truly just, and have spent their life serving others, the hall creates the illusion of their biggest fantasy coming true. The PC imagines spending the rest of their life happy and fulfilled. In reality, the PC is left standing their slowing dying of dehydration, lack of food, and lack of sleep. Eventually their body shuts down, killing them without them ever knowing what actually happened. (anyone who tries to enter the room to save their friends suffer the same fate). If someone was to view the room without the enchantment it'd be piled high with the bones of adventurers who never made it past this first trap.

Hmmmm, that one's a classic. Kind of easy to avoid with a good enough save but might be able to make it nasty. Maybe have it immediately after The Castle Hall and it gets harder to resist the /less/ people you've killed. So the party member able to open the door in The Castle Hall will promptly be shut down by The Hall Of Just Rewards. Oh! Bonus points if Just Rewards convinces them to close the door behind them! The only way to get the raging barbarian out of The Castle Hall is if he leaves the Hall BEFORE the cleric enters the Hall of Just Rewards!

...Also you've suddenly got me trying to come up with a trap that scales based on the value of the gear that the PCs are carrying. Maybe summon a mimic or rust monster or both that scales based on the value of each item you're carrying and have them try to consume it. No problem for anyone that runs around punching their enemies while naked, but the wizard and fighter are going to have issues with all their fancy toys.


Re the commoners getting in, if they're slaves it's fairly easy -- the boss has given them a magical brand that has horrifying negative effects on them but also lets them pass through the traps safely.

Your players won't want the brand (make it something ridiculous like "INT and CHA are reduced to 1, affected loses the ability to speak, cannot be removed even with a Wish spell") but it explains how everybody is getting in and out.

My main issue with the idea of just using a brand or other magical mark is that it opens the opportunity for other people to point and say "This will get you in" and then prepare themselves to do lots of damage once they're where they want to be. The good guys can slap the brand on then explore the castle with minimal problem, then once they've found the Evil Dude do something to restore themselves and murder him. Evil Dude doesn't want that. Evil Dude wants a castle that good guys just won't be able to get through that also will leave his slaves alone.


I was coming to say this. If it takes flight to enter the castle grounds, then have the castle itself be an image, coming in from another realm via giant portal.

That realm? Ravenloft. Nobody ever comes back from Ravenloft. Hos are all about the sexy undead.

If your players dare try for loot? Boom. Stuck in Werewolfville. Countotopia.

Ravenloft would be great, but the main problem is that the plane this castle is on is already similar to Ravenloft. It was sealed off from interplanar travel (excluding things like the Astral Plane and the Shadowfell, but those exclusively match the primary plane and have no access to the outer planes) specifically to keep Evil Dude inside. Like Ravenloft, creatures can be sent to it but nothing can get back out once it's there. Leads to interesting situations regarding the various outsiders that live there and their ability to summon more of their friends.

[Deathtongue]

I always find it amusing when DMs design traps that have much more utility and value in of itself than whatever it was intended to guard. Talk about getting the cart before the horse.

"I've built a trap that automatically and without an upper limit summons threatening copies of past opponents and prevents assistance! This thing is strong enough to threaten ancient white dragons! They sure won't be getting their hands on my +2 rapier and my Bracers of Defense!"

[furby076]

I like the creativity of the traps, but making them impossible to pass is kinda pointless to even make. Why bother with it, or heck, anything beyond the gate or first hall?

Maybe make the place somehwat reasonable so it can be advetureable. They just have to figure out the trick to each room (give 2 to 3 hints).

Also, the summon creature but remove temp xp is problematic for me. 1)xp is metagame. How did said owner create such a construct? 2)it may be pointless: "you temporarily lose 100 xp". Player "ok....and i smite the creature". 3)just a nightmare to track. Slows things down

If you really dont want them in there, then dont let them. Just say they cant figure out how to get in.

If you are hell bent on this, then make sure to let them take frequent ling rests and find powerful restorative stuff. Tpking the party can mess up a ling term campaign

[Hrugner]

I like the creativity of the traps, but making them impossible to pass is kinda pointless to even make. Why bother with it, or heck, anything beyond the gate or first hall?

Maybe make the place somehwat reasonable so it can be advetureable. They just have to figure out the trick to each room (give 2 to 3 hints).

Also, the summon creature but remove temp xp is problematic for me. 1)xp is metagame. How did said owner create such a construct? 2)it may be pointless: "you temporarily lose 100 xp". Player "ok....and i smite the creature". 3)just a nightmare to track. Slows things down

If you really dont want them in there, then dont let them. Just say they cant figure out how to get in.

If you are hell bent on this, then make sure to let them take frequent ling rests and find powerful restorative stuff. Tpking the party can mess up a ling term campaign

An impossible to pass trap is a non-metagame way of not letting the players figure out a way in.

[Coidzor]

An impossible to pass trap is a non-metagame way of not letting the players figure out a way in.

Yes, instead it's a bad thing to do because it actively taints the metagame.

It's punishing the players for trying to play the game, which is breaking into places that no one has ever returned from, killing the monsters there, and taking their stuff.

Instead, since this location has no importance to any story and cannot be accessed, the location has no reason to exist or for OP to narrate about it.

[Hrugner]

Instead, since this location has no importance to any story and cannot be accessed, the location has no reason to exist or for OP to narrate about it.

If that's the case, then sure. There's no way of knowing why the DM put the place there though and your analysis hinges on the assumption that he has no purpose.

[MaxWilson]

Hall Of Just Rewards

This magical chamber measures the worth of any character that enters. For those that are truly just, and have spent their life serving others, the hall creates the illusion of their biggest fantasy coming true. The PC imagines spending the rest of their life happy and fulfilled. In reality, the PC is left standing their slowing dying of dehydration, lack of food, and lack of sleep. Eventually their body shuts down, killing them without them ever knowing what actually happened. (anyone who tries to enter the room to save their friends suffer the same fate). If someone was to view the room without the enchantment it'd be piled high with the bones of adventurers who never made it past this first trap.

In many ways I think the Mirror of Erised is kind of boring and cliche, but the intersection with D&D as a game makes this potentially awesome. That is, when they look in the mirror, the DM puts a note on the table, face down, saying "read after death." Then he says, "You have won the castle! You gain 3 million XP, and hit 20th level, and receive a magic item of your choice, to be named later--when you decide what you want, tell me and it will have been there all along. Now, what do you want to do next?"

Whatever it is they want to do, play it out and grant them success. If die rolls are involved, don't bother having the players roll: they always get natural 20s, and their enemies always get natural 1s.

If anyone dares to kill themselves, they get to read the note, which says, "Everything that has happened since you looked into the mirror is a fantasy. You wake up, shuddering and queasy. Your companions still stare raptly into the mirror. Do not speak of this aloud, but pass me back another note saying what you want to do next."

[MadBear]

In many ways I think the Mirror of Erised is kind of boring and cliche, but the intersection with D&D as a game makes this potentially awesome. That is, when they look in the mirror, the DM puts a note on the table, face down, saying "read after death." Then he says, "You have won the castle! You gain 3 million XP, and hit 20th level, and receive a magic item of your choice, to be named later--when you decide what you want, tell me and it will have been there all along. Now, what do you want to do next?"

Whatever it is they want to do, play it out and grant them success. If die rolls are involved, don't bother having the players roll: they always get natural 20s, and their enemies always get natural 1s.

If anyone dares to kill themselves, they get to read the note, which says, "Everything that has happened since you looked into the mirror is a fantasy. You wake up, shuddering and queasy. Your companions still stare raptly into the mirror. Do not speak of this aloud, but pass me back another note saying what you want to do next."

I love that spin on it.

In my mind I was thinking less of the Mirror of Erised, and more of Total Immersion Video Game, from Red Dwarf (http://reddwarf.wikia.com/wiki/Total_Immersion_Video_Game)

[Coidzor]

If that's the case, then sure. There's no way of knowing why the DM put the place there though and your analysis hinges on the assumption that he has no purpose.

If it had any true importance to the game, it would be a location they could actually visit instead of being an attractive nuisance that's just a Rocks Fall, You Die wrapped up in fancy bows and ribbons.

[Temperjoke]

As for how the slaves were free to travel, they could have been given a magical brand on their forehead which, combined with magical shackles that only activate when properly worn on a single person, deactivates traps for just them. After all, how likely is an adventurer to brand themselves and wear a full set of shackles that they probably can't escape from?

Also, as for defenses, what about patrol golems that attack anything that isn't supposed to be there (the aforementioned markings for slaves would protect them). The golems could be magic-reflecting and immune to all weapons except adamantite ones.

You could also pull a Cave of Wonders from the Aladdin movie, where touching anything other than the lamp causes everything to turn to lava. Admittedly, you don't need a lamp, the whole treasure temptation would easily be enough to kill most adventurers, especially if there was nothing to warn them, and they were tricked into thinking it was a vault.

[Kyouhen]

I like the creativity of the traps, but making them impossible to pass is kinda pointless to even make. Why bother with it, or heck, anything beyond the gate or first hall?

Maybe make the place somehwat reasonable so it can be advetureable. They just have to figure out the trick to each room (give 2 to 3 hints).

Also, the summon creature but remove temp xp is problematic for me. 1)xp is metagame. How did said owner create such a construct? 2)it may be pointless: "you temporarily lose 100 xp". Player "ok....and i smite the creature". 3)just a nightmare to track. Slows things down

If you really dont want them in there, then dont let them. Just say they cant figure out how to get in.

If you are hell bent on this, then make sure to let them take frequent ling rests and find powerful restorative stuff. Tpking the party can mess up a ling term campaign

Each of the traps will still have some form of trick to make them passable, such as knowing that whoever doesn't have a monster attacking them can just open the door for everyone else. The loot the players can find in the castle (which is absolutely worth it, though rather tainted by evil) makes up for the frustration of getting through the dungeon. In the case of how the constructs are created, the trap digs through their memories and rips the memory out to create shadows of anything they've killed. Wisdom saves are involved to modify what result on the chart they get, forcing the trap to summon weaker enemies if they roll well and stronger if they roll poorly.

It isn't that I don't want them in there. It's that the campaign is open-world. The players will never be forced to go in there, but it exists for world-building reasons and if the players decide to try to get in they're welcome to do so. Simply saying "It's impossible" just isn't fun.

Frequent rests won't be hard. There's next to nothing still alive inside the castle, just a large number of traps. I want the thing to be more a case of survival. How long can they survive trapped inside the castle? That last trap nearly killed us, do we /really/ want to go deeper when we still have to go back through that trap to leave? General assumption is that everyone else who went in got greedy and died. Anyone who went in and came back out decided not to let anyone know they went in so they can keep the information to themselves, then went back in and got stuck and died. (Actually, now that I think about it I might stick in an NPC or two that are immortal but found themselves stuck and could neither move forward nor back. Maybe an elf that has gear to provide food and water but lost the rest of his party and can't get any further.)


In many ways I think the Mirror of Erised is kind of boring and cliche, but the intersection with D&D as a game makes this potentially awesome. That is, when they look in the mirror, the DM puts a note on the table, face down, saying "read after death." Then he says, "You have won the castle! You gain 3 million XP, and hit 20th level, and receive a magic item of your choice, to be named later--when you decide what you want, tell me and it will have been there all along. Now, what do you want to do next?"

Whatever it is they want to do, play it out and grant them success. If die rolls are involved, don't bother having the players roll: they always get natural 20s, and their enemies always get natural 1s.

If anyone dares to kill themselves, they get to read the note, which says, "Everything that has happened since you looked into the mirror is a fantasy. You wake up, shuddering and queasy. Your companions still stare raptly into the mirror. Do not speak of this aloud, but pass me back another note saying what you want to do next."

...I like this idea. This is totally a thing that's happening now.

[Falcon X]

There is a magic detector in a room. If it detects anything magical, 500 kg metal gates drop at both entrances of the room before locking into place, trapping the characters hermetically. It is impossible to teleport out of the room, or use magic to go to another dimension/go through the walls/etc.

The doors won't open until everyone in the room is dead.
There's got to be some way out.
What if you can only leave if you are no longer carrying the magic items. Thus, this is the magic storeroom of tins of magic items. Only a key hidden deep in the castle can turn off the effect.
And hey, now the players proceed forward with no magic items.

[furby076]

Each of the traps will still have some form of trick to make them passable, such as knowing that whoever doesn't have a monster attacking them can just open the door for everyone else. The loot the players can find in the castle (which is absolutely worth it, though rather tainted by evil) makes up for the frustration of getting through the dungeon. In the case of how the constructs are created, the trap digs through their memories and rips the memory out to create shadows of anything they've killed. Wisdom saves are involved to modify what result on the chart they get, forcing the trap to summon weaker enemies if they roll well and stronger if they roll poorly.

It isn't that I don't want them in there. It's that the campaign is open-world. The players will never be forced to go in there, but it exists for world-building reasons and if the players decide to try to get in they're welcome to do so. Simply saying "It's impossible" just isn't fun.

Frequent rests won't be hard. There's next to nothing still alive inside the castle, just a large number of traps. I want the thing to be more a case of survival. How long can they survive trapped inside the castle? That last trap nearly killed us, do we /really/ want to go deeper when we still have to go back through that trap to leave? General assumption is that everyone else who went in got greedy and died. Anyone who went in and came back out decided not to let anyone know they went in so they can keep the information to themselves, then went back in and got stuck and died. (Actually, now that I think about it I might stick in an NPC or two that are immortal but found themselves stuck and could neither move forward nor back. Maybe an elf that has gear to provide food and water but lost the rest of his party and can't get any further.)



...I like this idea. This is totally a thing that's happening now.

Just remember to drop clear hunts, 2 to 3. Remember, just because you know how the hint solves the puzzle doesnt mean anyone else will get it.

Make sure your stuck immortal has gone crazy from being in isolation for eons

[dgnslyr]

Somehow, creating a perfect network of traps just seems like an exercise in futility; people innovate but traps don't. It's said that a castle's defense is only as good as its defenders. The boring answer would be to have soldiers inside that are as strong or stronger than the adventurers outside, but if you can't have a living, thinking garrison, then maybe an unthinking one could work. For example, low-level golems regularly patrol the halls, while big threats call the big hitters into action. Maybe even judicious use of anti-magic fields and disjunctions when unfamiliar magical auras are detected? A commoner with a bucket and mop, on the other hand, is pretty obviously a non-threat and can freely mop away, unmolested by security.

[Kyouhen]

There's got to be some way out.
What if you can only leave if you are no longer carrying the magic items. Thus, this is the magic storeroom of tins of magic items. Only a key hidden deep in the castle can turn off the effect.
And hey, now the players proceed forward with no magic items.

...Idea!

Heavy Magic Field
Amplifies the magic of magic items and spells, while compressing the magical emanations. The end result is that anything affected by a spell and magic items is coated in a thin layer of "heavy magic". The weight of a magic item is increased by an amount equal to 100lbs per level of every spell required to create the item, while the weight of anything affected by a spell is increased by 100lbs per level of the spell.

Might decide that the weight boost should be equal to the value of the item, not sure. Would need to run some math to see just how painful this would be. In any case the PCs would need to abandon a pretty significant number of their items to get out, and anyone that's buffed themselves are stuck there until the buffs wear off.