Dream Not of Other Worlds -- A Selection of Portable Demiplanes

...Heav'n is for thee too high
To know what passes there; be lowlie wise:
Think onely what concernes thee and thy being;
Dream not of other Worlds, what Creatures there
Live, in what state, condition or degree...
-- John Milton, Paradise Lost, Book VIII

From the TNG episode “Remember Me"

One of my favorite things about the assumed setting of D&D is the potential for planar travel. And one of my favorite aspects of that has long been the idea of demiplanes -- small universes of limited scope that can pretty much range from “big but not infinite" to “comically small". They're often deeply weird, or have some specific purpose that almost-but-doesn't-quite make sense in our Earth logic. Which is, of course, what makes them fun.

Here, I'm presenting a handful of demiplanes that can be accessed through portable magical items -- making them, essentially, “pocket dimensions" in every sense. On that note, let's start with the:

Pocket Necropolis

Source.

The Pocket Necropolis can be accessed through a small stone talisman that resembles an ancient tomb -- which, appropriately, is small enough to fit in one's pocket. Uttering a command word allows one to enter the Necropolis, where they will find... a large, dusty, stone chamber. There are multiple exits from this chamber, however, and each of those leads to long, branching corridors lined with heavy stone doors, each of which is inscribed with a name. (All inscriptions, engravings, &c. produced by the Pocket Necropolis appear in the native language and writing system of the reader.)

Each of the stone doors leads to a tomb, in which one will find a stone sarcophagus and associated burial items.¹ If someone is so rude as to open the sarcophagus, they will find that the body within is preserved under the effects of a permanent gentle repose. On the sarcophagus is engraved an epitaph, giving a general (if somewhat exaggeratedly positive) idea of who is interred there, and all around the room in shelves and niches are items of personal significance to the deceased. Examination will reveal that many -- if not all -- of these items are clever counterfeits, created by the Necropolis because it doesn't have access to the real thing. It should be noted that the Necropolis's counterfeiting ability does not extend to enchantments, but is otherwise extremely thorough -- if it makes a copy of a book, the entire text will be accurately reproduced. If that book was supposed to be magic, well, it's just not. It should also be noticed that the Necropolis will be pleased if you go out and find that particular copy of that book for it so the tomb can be better stocked. That kind of leads into the next relevant item -- the Necropolis is aware of people wandering about inside of it, and has opinions about them, which it expresses via its internal guardians.

Source.

The Necropolis's internal guardians can take the form of any type of undead, with the same stats as they would ordinarily have, with only one exception -- they are under the control of the Necropolis, which can speak through them. In the case of intelligent undead -- spectres are a particular favorite of the Necropolis -- they still possess the intelligence and personality of whoever they “were" in life, but obey the orders of the Necropolis unquestioningly. These guardians are always patterned after individuals that the Necropolis has entombed, but, again, this is a matter of clever counterfeit. The Necropolis is of the opinion that it is extremely disrespectful to raise the dead, as undead or as living beings, and would never undermine itself by doing so -- the “undead" internal guardians are created out of whole cloth.

The Necropolis is pleased if you respect its tombs. It wants you to leave the grave goods where they are and not mess with the bodies in any way. As mentioned above, it likes it when you help stock the tombs as well. It will become violently displeased with you if you make a habit of stealing the grave goods or dare to raise or animate any of the tombs' occupants. The Necropolis is also pleased when you bring it more bodies.

If you leave any dead body unattended in the entrance chamber, it will vanish within 24 hours, when the Necropolis takes it and makes a new tomb for it. It unerringly knows enough about the dead to engrave the epitaph and stock the tomb; this can function as an information-gathering device for the PCs, with the caveat that it's really difficult to find the new tombs. The Necropolis, you see, does not have empty tombs you can stake out; when it needs to inter a new body, one of its many branching corridors grows slightly longer and a new tomb appears, in whatever spot seems like the best place for that person to be -- the Necropolis has a system for organizing its tombs, but what that might be is largely opaque. As a result of this mechanism, the Necropolis is huge and has a fairly non-intuitive layout.

Source.

The Necropolis generally only provides tombs for sapient beings. If you leave bodies of creatures with an Intelligence of 5 or lower in the Necropolis, it starts getting picky with how it treats them. They still get a tomb if the Necropolis sees them as exceptional in some way, though the odds of that go down as their Int score decreases -- a griffon (Int 5) has a pretty good chance of being assigned its own tomb, but a lizard (Int 1) had better be one heck of an impressive lizard. If the body doesn't meet the Necropolis's standards in this respect, instead of getting an individual tomb, it will appear in one of the Necropolis's storerooms. These are large chambers in which the walls are covered in niches of various sizes, each of which holds the body of an animal, cleaned, repaired, and under the effects of gentle repose. There are epitaphs carved over each niche, but they are very brief -- a name, if the creature had one, and a one-sentence description of their life & death.

You can theoretically use the Necropolis for storage, like a bag of holding, but there are some caveats. If you leave something in there that has personal significance to one of the bodies interred -- which becomes pretty likely if you start tossing in bodies of creatures you killed and/or looted -- the Necropolis will take it to be part of that tomb's collection of grave goods, and will get upset if you try to take it back. Second, and perhaps more worrying, is the fact that you're not the only people with access to the Necropolis.

Parties who take the time to explore the Necropolis fully will eventually discover several other empty chambers like the one they started in, scattered randomly about the complex. Each of these is an entrance chamber connected to another stone talisman just like the one the PCs have. There are dozens of these talismans, spread out over incredible distances, and many of them are probably in use. So one of the dangers with using the Necropolis as storage or as a safe place to rest is that you're not alone in there. And if some of the other people in there are better about following the Necropolis's rules, it might take sides.

You know, one of these.
Source.

Nackleshire²

The item that allows you to connect to Nackleshire is a mottled, off-white sphere that kind of resembles one of those Himalayan salt lamps you see everywhere these days. Examining it closely will reveal very small runes engraved into its surface; if any of the PCs can read them, they provide the command word to activate the item.

Once a day, the Nackleshire item allows the user to summon a salt mephit, who will remain for one hour before vanishing. The mephit will obey your orders, but may or may not be happy about it; if the PCs order the mephit to do something that is overtly dangerous or against the mephit's personal moral code, the GM is encouraged to resolve this through giving the mephit a Will save to resist, or making opposed Charisma checks, or similar. Over time, as the PCs use the item, they will find that Nackleshire contains exactly twenty mephits with differing skills and personalities³, and they get a random one each time. Whenever a mephit vanishes or is killed, they reform in Nackleshire, where apparently they have some kind of social life -- they tend to report back on their experiences, talk to each other, and form opinions on the PCs. If, over a long period of time, they feel that the PCs are treating them well and showing adequate respect, they may unlock some of the item's other abilities.

From the 3rd edition DMG.

The second ability, which requires a different command word and the permission of the mephits, is a variant of the classic magic item Daern's Instant Fortress. The differences are largely aesthetic: the tower and its interior furnishings have the same mottled, off-white appearance as the sphere. There are a couple functional differences, however. First, you can only use it once a day⁴, and it dematerializes after eight hours. Second, the tower is not expanding from a compacted state, but being shifted over from a demiplane. This has a couple obvious results: it doesn't deal bludgeoning damage as it expands, but just appears around the person using it. Also, when you dismiss it, you can leave inanimate objects in there without having to worry about them getting trash-compacted. The PCs may well find furnishings, books, &c. left in there by previous owners. Third, it comes with a butler; one of the twenty mephits in Nackleshire is employed as the butler and caretaker of the tower, and will happily accommodate the needs of the PCs. He can even summon them some food, if they need it, though anything he summons tends to be just a little bit too salty.

The third and final ability allows the PCs to enter Nackleshire themselves. Like the second ability, you can only use it if the mephits like you enough to give you that privilege. Once per day, the owner of the item can open a portal to Nackleshire. (There is no limit on how often you can open a portal back out.) In Nackleshire, there really isn't much to see; there's the tower, and outside of that, the plane is a lot like living in a snow globe filled with salt and friendly mephits. The benefit of using this ability, of course, is nothing to do with the scenery -- it's a more-or-less unassailable refuge, because even if someone would think to look for you in some random demiplane, getting there would be quite difficult. (And even if someone does manage to plane shift in, you have a fortress and a platoon of mephit allies.

Source.

Wandering Oubliette

This is an item you don't so much own as encounter. It's a portable hole that's gotten too big for its britches, probably as the result of someone trying to improve the original item. The Oubliette wanders, autonomously, seeking out creatures to swallow; it has an animal-level intelligence, and can enact some basic hunting strategies, such as sticking to dark, enclosed spaces so it can blend in and ambush prey. It manifests as an oversized portable hole, more than ten feet in diameter and some hundred feet deep.

Inside the Wandering Oubliette, you will discover circular walls of smoothly-polished stone, that curve towards the smaller opening at the top, rather like the inside of a bottle. It is intentionally difficult to climb out, and the floor is likely littered with the remains of the Wandering Oubliette's previous prey. This is the entirety of the little extradimensional space in which you have been entrapped. Lucky for you, you probably don't have to worry about running out of air -- the Wandering Oubliette rarely bothers to fold itself up. Unluckily for you, it really does wander; through some unidentified mechanism, the Oubliette seems able to teleport from one dark, enclosed space to another on a fairly regular basis. So if you do manage to climb out, you may find yourself in a different place entirely.

Ebu-Gogo Talismans

Hundreds of millennia ago, another people lived in the land that we now occupy. But, for one reason or another, they were pushed out, and the people who live here now supplanted them. There are virtually no remaining records of these people, except in abstracted legends about predecessor races, which refer to them as Ebu-gogo. When the Ebu-gogo recognized that they were losing the long struggle for their land, they turned to their shamans, who were said to possess strange powers beyond what any modern cleric can achieve. These shamans built refuges, demiplanes just big enough to support their tribes, and the Ebu-gogo fled into them. The entrances to these demiplanes were keyed to small, carved talismans that were enchanted to survive the millennia and then hidden -- so that, if any of the Ebu-gogo needed to leave and return, they would be able to use the talismans to do so.

Source.

And, of course, they do occasionally come and go. Sometimes, for one reason or another, food is scarce in their demiplane one year -- it's rare, but it happens -- and a raiding party needs to pop out and loot some supplies from the outside world. Sometimes a younger member of the tribe gets curious, wants to see what it's like outside, and goes out exploring. Sometimes, the tribe is so enraged by a member's behavior that they are exiled. Sometimes, there's an inbreeding issue and someone needs to go find & court members of another tribe. And sometimes, there's a matter of the Ebu-gogo's unique version of population pressure.

When the demiplanes were originally built, the shamans made them exactly big enough to sustain a nomadic lifestyle for their tribe. As long as the population of the tribe never grew beyond where it currently was (usually between 100 and 200), they should be able to live off the land indefinitely. And to make sure that such a thing never came to pass, part of the way the demiplanes function is that they will not allow new children to be born if it would increase the population past the original carrying capacity of the demiplane. Usually, the Ebu-gogo can work with that, and when they bump up against the population cap, a sort of automatic birth control switches on. However, sometimes, due to unfortunate timing, an Ebu-gogo woman finds herself already pregnant when they reach the population cap, and is then stuck with a child she cannot give birth to unless someone else dies. Since an indefinite pregnancy would be very unpleasant, a solution must be found -- and that solution is generally for someone to volunteer to leave to make room for the baby. (If nobody volunteers, the mother will probably end up leaving.)

Ebu-gogo, or rather, an artist's
recreation of Homo floresiensis.
Source.

The other side of Ebu-gogo population caps is that nobody can enter the demiplane if it is at its maximum population. This means that the aforementioned unfortunate exiles are usually trapped outside permanently, and are forced to find a way to live in a world completely different from the one they and their ancestors spent their entire lives in. It also means that, even if an outsider finds one of the talismans, there's a chance that it just doesn't work -- the demiplane might be full and nobody can get in even if they know how to work it.

The Ebu-gogo themselves possess a striking appearance. They are small -- about the same stature as halflings -- dark-complected, and very hairy. They have unusually long limbs for their size, and notably large mouths. They're generally decent folks, assuming you're speaking to someone who came out of the demiplane voluntarily and not an exiled criminal. However, they tend to be a little odd by human standards -- after all, if you're talking to one, one of the two of you is probably a recent immigrant to another reality. Their longer legs and arms make them excellent hunters, able to run at impressive speeds for their size and throw a spear with terrifying strength.

Source.

The reason they seem a little odd, other than normal degrees of cultural divergence, is because where they come from, reality works differently. When the ancient shamans built the demiplanes to which they retreated, they modeled them after the tribe's beliefs, teachings, and understanding of the world. If they believed that the world was carried on the back of a turtle, that's what the world was really like inside the demiplane. If they believed the shaman had to propitiate the sun to make it rise each morning, then the shaman really had to do that or they'd be stuck in the dark. The whole of their miniature world operates on a different logic than ours, and after living there for uncounted generations, that's their normal.

---

1 The size of the tomb chamber scales roughly with the size of the person interred there -- a human would get a chamber roughly ten feet to a side, but a storm giant's chamber would be thirty-five feet to a side.^↩
2 I posted this idea on the Giant in the Playground forums a while back, and it subsequently received some limited use in a campaign log by another GM here.^↩
3 GMs are encouraged to note up a list of different mephits with divergent personalities and capabilities for this purpose.^↩
4 GMs whose campaigns might be broken by allowing the players a refuge every night are encouraged to reduce this to once a week.^↩

Use-Impaired Magic Items II

The previous list of “use-impaired" magic items is here. It gets a sequel because these things are just so damned fun to write. If you missed the last one or don't feel like clicking through the link, these are magic items that aren't necessarily useless,  but are inconvenient, non-intuitive, or just plain weird -- as liable to frustrate your players as help them.

Septum Piercing of Luck Exchange

This item of jewelry makes the wearer incredibly, unbelievably lucky. They have advantage on every roll they make, because things just tend to work out for them. Sounds fantastic, right? Well, there are a few drawbacks.

First, of course, it absolutely has to be worn as a septum piercing for it to work. Which doesn't seem like much of a drawback, because septum piercings are badass, right? Right, but that makes getting around all the other drawbacks much more complicated.

Image from this Etsy shop.

See, all that luck can't just be created out of thin air. It has to come from somewhere. This is why Septum Piercings of Luck Exchange always come in pairs, and have to be worn and activated in pairs. So as a result of the first two, it's virtually impossible for an unscrupulous PC to force someone else to wear the other one in the pair -- just imagine one of your players trying to say, “I sneak up and pierce his septum while he isn't looking". And tricking someone else into wearing it will likely occur to them, because the reason the second one is required is to provide a source for the luck -- the wearer of the other ring in the pair has disadvantage on all their rolls.

“Fine, fine," the PCs might say, “we'll pay some random NPC to wear the other one; surely we can afford to compensate them well enough for the inconvenience of bad luck." Well, not so fast. And don't let them call you Shirley (unless that's actually your name). At sunrise every day, the two rings in the pair switch between “lucky" and “unlucky"; essentially, the two people wearing them have to trade off on days of good luck and days of bad luck. So it balances out -- half the time you're supernaturally lucky, half the time you're supernaturally unlucky.

Naturally, PCs will try and find a way to get around this. Maybe they'll suggest hiring a henchman to wear the other one and just swapping each morning so the “lucky" one is always on the PC. First of all, ew; that's a good way to get a nasty infection. Second, well, the GM is encouraged to find any way to keep the "I only wear it every other day" plan from working. These can range from the simple to the hilariously sadistic. Some examples from various points on that spectrum:

• The enchantment “remembers" who's “supposed" to be wearing each ring, and still works the same if you swap, or refuse to wear it on “unlucky" days. Getting it to stop stealing your luck requires ending your attunement with it, and then you can't re-attune again.
• Removing one always requires passing a Will save at disadvantage.
• Just ask yourself, “how would the universe react to a sudden, and increasing, imbalance of bad luck?" Be imaginative. Maybe the bad luck starts to escape the ring, “grounding" itself in anyone nearby with catastrophic results. Maybe it just quietly builds, and builds, and builds, until something massively improbable and fatally awful happens, like the countryside for a mile around getting spontaneously sucked into the Abyss -- hey, sometimes weird planar crap just happens, and it's your bad luck that it happened at the specific place and time you happened to be. Go nuts; I'm sure you can think of something far worse than I can.

Talisman of the First Deception

The Talisman of the First Deception resembles a small egg carved of green stone, slightly smaller than a hen's egg. Careful examination will reveal small, subtle etching near the larger end that says, in some arcane script that would be familiar to any wizard in your campaign setting: 

One lie to be believed by all who hear. Single use only. -- Broneden

Attempts to identify the item will inform the PCs that it is essentially a single-shot, extra-strength, potion of glibness. It will work for exactly one spoken lie, and gives such a massive bonus to the user's Bluff check that you might as well not even roll. (After use, it cracks open, leaving the PC with several shards of green stone eggshell.)

If the PCs are exceptionally skilled, or roll particularly high on identifying the item, they may get the full picture, and information about its additional properties. Otherwise, their knowledge stops with what is above.

The creator of this helpful little device, one Broneden, went just a little bit overboard -- which is why some of these single-use talismans are still just lying around. It works, but it also produces what could be a life-long annoyance. Broneden, see, wanted to make sure that the target of the lie couldn't be set straight by someone else -- if you bluff the prison guard, and he decides to check with his superior, you're screwed -- so he added a sort of contagion effect.

Etching (transcription)

Not only does everyone who hears the lie believe it to be true (Note: everyone. Even people you're not trying to convince. Even people who know for a fact that what you're saying is false. Even people with whom you discussed this plan and whom you explicitly told “I am going to tell the following lie." Everyone), but anyone they speak to will also believe that lie to be true. And then anyone those people speak to. Once the effect gets just a little momentum going, it spreads like a plague. It doesn't even require that those affected speak about the lie -- any communication at all counts. The only person this doesn't affect is the one who told the original lie. (Which means that talking to them doesn't count for the purposes of the lie's contagion -- but talking to their party members probably does.)

The result of this, essentially, is that for the rest of the original liar's life, anyone who's spoken to someone who's spoken to someone who's spoken to someone ... and so on ... who's spoken to someone who's spoken to someone who was present when the lie was told will firmly believe that the contents of that lie are completely true. Even if they have no context for that information, have no idea who any of the relevant people are, &c. &c. If you used the Talisman to, say, convince someone you were a paladin, you will spend the rest of your life running into people who have never met you and don't know anything about you, but as soon as you introduce yourself, they'll respond with “oh, you're a paladin, right?" Because somewhere inside their head it is indelibly written that “[John Smith] is a paladin," and they know you're the [John Smith] in question, but they don't know why they know that.

Ring of Command Insects

This is one of those “exactly what it says on the tin" moments. Once a day, you can use this ring to speak with, and give orders to, any insects within line of sight. The spell wears off as soon as they've done whatever you asked them to do.

Image from this Etsy shop.

There are a couple of catches, however. First, insects are pretty dumb. Technically, by the rules, they're “mindless", so part of the ring's magic is giving them a few temporary Intelligence points just so they can follow instructions. Just a few, though, so your instructions have to be really simple for them to understand.

Second, they may be compelled to obey you, but they resent it. And they resent being briefly given an Int score just to do your bidding. While they can't not follow your instructions to the letter, they will “misunderstand" whenever possible, and honestly won't put a whole lot of effort into doing things right. So you've got to be careful with your instructions and avoid entrusting them with anything too complicated or high-stakes.

This is another item I've actually used in a campaign before; the PCs quickly came to the conclusion that having the insects do anything was liable to backfire, and just used it for information gathering. They referred to it as the “Ring of Ask Bugs".

Axe of the Apostle

This is an elaborately-decorated masterpiece of a weapon, sharp and sturdy, in every aspect the perfect axe for someone who wants to cut some seriously bloody swathes across the landscape. It is also so holy that anyone sensitive to these things can feel sheer Good rolling off it in waves. This, you see, was once the weapon of one of the greatest travelling clerics of her generation, St. Ujali, and functions as a +3 holy battleaxe.

St. Ujali showing the axe to a travelling companion.
(Actually detail from this painting)

So what's the catch? Well, St. Ujali was a pacifist. A full-on, uncompromising, “sweep the ground in front of you so you don't step on bugs" pacifist. And her axe carries on that legacy. It is physically impossible to use the axe to harm anything living OR anything with an Intelligence score -- so it can basically only be used on undead or constructs, and even then only the mindless varieties. If anyone tries to use the axe against anything that doesn't fit that description, the axe will deform and flow like liquid, shifting so no part of it actually comes into contact with the intended target. It is thus completely impossible for the axe to physically harm a living and/or sentient being of any kind, and any attempts by the wielder to get around this property of the axe are unlikely to work; the axe has been known to manifest previously-unknown properties in order to maintain its absolute pacifism.

Of course, it is an intrinsically valuable item, being beautiful, magical, and historically significant, so you could probably sell it for a good sum. Finding a buyer who is willing to pay its value might be difficult -- St. Ujali's order all take a vow of poverty, so you're not going to sell it to any temples. Really, the only realistic option is to hope some eccentric private collector really, really wants this thing. Plus, it's not exactly labelled; there's no reason the PCs would know it has historical significance unless they do some research first -- or someone makes a really good bardic knowledge roll.

Actual size.
(Image from the Smithsonian NMAI)

Talisman of Deanatification

This small duck, woven from dried reeds, can cast break enchantment. There is no limit on how often it can be used per day, or how many charges it has. However, it only works if the enchantment being broken involves being turned into a duck. If someone has baleful polymorphed you into a duck, this is exactly the magic item you need, but -- barring potential fringe cases -- that's pretty much the only situation in which it's useful at all.