How to get into a Mordenkainen's Magnificent Mansion

[Marshall Gatten]

By the way, all three versions of Genesis are in the d20 SRD. The arcane version is from the Epic Level Handbook, but like some other things from that book, is not actually epic.

Genesis grows the plane at a cubic foot per day and is not one level higher, but two levels higher. It can't create living things (like food) and can't create structures. But you're saying that Magnificent Mansion, at two levels LOWER, creates 3000 cubic feet of new plane in a standard action and populates it with food and structure? And you don't think that sounds unbalanced? I see Genesis as confirmation that Magnificent Mansion surely can't possibly create its own plane.

Rope trick says nothing of creating extradimensional space - only that the rope reaches into extradimensional space.

A portable hole does say it "causes an extradimensional space to come into being", but it also describes a kinship with bags of holding (which don't have that language) that squarely connect their activities to the astral plane. I even remember something from some TSR publication long ago about Astral travelers being able to sense bags of holding and portable holes though I don't recall the specifics.

The links to Pathfinder's Create Demiplane are a stronger argument, especially since its a lower level spell. But again, it takes hours to create a comparable-sized space and the space is featureless and sterile. Magnificent Mansion takes a standard action and comes with food and structure. I can't see any way to justify saying that it also creates the plane it exists on. Certainly not in a standard action.

 

[Tuft]

So the entry point is still there, much like a Rope Trick. Both should be subject to Dispel on the same basis.

Or just gather something nasty near the portal - they can only stay inside until duration ends. And, since it is an extradimensional space, where are they leaving their Haversacks, Bags of Holding and Portable Holes?

Think it has to be specifically a portable hole and a bag of holding that intersects for bad things to happen, not not just any extradimensional spaces.

Could not find the corresponding text from the 3.5, but the Pathfinder SRD has this text:

A number of spells and magic items utilize extradimensional spaces, such as rope trick, bags of holding, handy haversacks, and portable holes. These spells and magic items create a tiny pocket space that does not exist in any dimension. Such items do not function, however, inside another extradimensional space. If placed inside such a space, they cease to function until removed from the extradimensional space. For example, if a bag of holding is brought into a rope trick, the contents of the bag of holding become inaccessible until the bag of holding is taken outside the rope trick. The only exception to this is when a bag of holding and a portable hole interact, forming a rift to the Astral Plane, as noted in their descriptions.

(From http://www.d20pfsrd.com/magic-items/wondrous-items )

 

[Marshall Gatten]

A number of spells and magic items utilize extradimensional spaces, such as rope trick, bags of holding, handy haversacks, and portable holes. These spells and magic items create a tiny pocket space that does not exist in any dimension.

That right there is the best argument so far against my point of view. If these spells and items "create a tiny pocket space" then so can Magnificent Mansion. Personally, I think that's wrong-headed and that the book should instead use the word "utilize" again, as it does in the previous sentence. But that moves it away from Rules-As-Written and firmly into house rule.

My hat is off to you. I love it when I learn new stuff. (But if it ever comes up in my own game, I'm still house-ruling that these items and spells access an already extant space. For all the reasons I've cited, I can't see a space this big being created from nothing in the time of a standard action - especially with food, structure, and even liveried servants.)

 

[Tuft]

My hat is off to you. I love it when I learn new stuff. (But if it ever comes up in my own game, I'm still house-ruling that these items and spells access an already extant space. For all the reasons I've cited, I can't see a space this big being created from nothing in the time of a standard action - especially with food, structure, and even liveried servants.)

Note that what I quoted was Pathfinder, not 3.5. There are lots of small differences...

 

[Marshall Gatten]

This all prompts a new but related question: If the Mansion is in a "pocket space that does not exist in any dimension" then what happens if the spell expires before everybody leaves?

A kind and benevolent DM would say that everybody gets dropped back into Prime Material. But that kind of presupposes that the extra-dimensional space has a temporal connection to Prime Material in some place other than the door. But pocket spaces, according to the rules, do not exist in any dimension.

If the space they are in ceases to exist, then do the characters and all their belongings also cease to exist?

My gut reaction is to say yes, and make sure the players are aware that they'd better get out of there on time.

 

[N'raac]

Think it has to be specifically a portable hole and a bag of holding that intersects for bad things to happen, not not just any extradimensional spaces.

Could not find the corresponding text from the 3.5, but the Pathfinder SRD has this text:

A number of spells and magic items utilize extradimensional spaces, such as rope trick, bags of holding, handy haversacks, and portable holes. These spells and magic items create a tiny pocket space that does not exist in any dimension. Such items do not function, however, inside another extradimensional space. If placed inside such a space, they cease to function until removed from the extradimensional space. For example, if a bag of holding is brought into a rope trick, the contents of the bag of holding become inaccessible until the bag of holding is taken outside the rope trick. The only exception to this is when a bag of holding and a portable hole interact, forming a rift to the Astral Plane, as noted in their descriptions.

I stayed away from Pathfinder specifically because its rules are either better spelled out or more lenient, from recollection of a prior discussion. I also recall an old Gygax suggestion (IIRC) that a Bag of Holding in a Bag of Holding overlapped magic and left enough space for, maybe, another coin or ring. In any case, if your spellbooks were in that Pathfinder Haversack, you can't study them inside the rope trick or mansion. At least you need not climb a rope to get into the mansion!

 

[Marshall Gatten]

The reason my question about the cessation of the pocket space and things inside it is relevant is because it speaks to the previous points upthread about preparing the return area instead of trying to storm the Mansion. If a high-level caster knows that his quarry is in a Mansion, and he knows where the door is (within 20'), and he knows that anything in the pocket space will cease to exist at the end of the Mansion spell, then his best bet at a TPK might be casting Dimensional Lock centered on the door's area.

It has a longer spell duration and so ensures that anybody trying to cross the threshold will be stuck in the pocket space until it ceases to exist. And, since the Lock exists on Prime Material, I'm thinking Dispel Magic cast from the pocket space probably can't reach it. (Dispel Magic doesn't mention any plane crossing.)

So, instead of "How to get into a Mordenkainen's Magnificent Mansion" the question becomes "How do you get out?"

So let's say you're in your MMM and you notice that the door won't open for you. Maybe you realize that it's because of a Dimension Lock on the other side, or maybe you don't. Regardless, how do you escape?

If there isn't a good backup means of escape, then MMMs might backfire and become an extremely deadly trap.

 

[Loren Pechtel]

The reason my question about the cessation of the pocket space and things inside it is relevant is because it speaks to the previous points upthread about preparing the return area instead of trying to storm the Mansion. If a high-level caster knows that his quarry is in a Mansion, and he knows where the door is (within 20'), and he knows that anything in the pocket space will cease to exist at the end of the Mansion spell, then his best bet at a TPK might be casting Dimensional Lock centered on the door's area.

It has a longer spell duration and so ensures that anybody trying to cross the threshold will be stuck in the pocket space until it ceases to exist. And, since the Lock exists on Prime Material, I'm thinking Dispel Magic cast from the pocket space probably can't reach it. (Dispel Magic doesn't mention any plane crossing.)

So, instead of "How to get into a Mordenkainen's Magnificent Mansion" the question becomes "How do you get out?"

So let's say you're in your MMM and you notice that the door won't open for you. Maybe you realize that it's because of a Dimension Lock on the other side, or maybe you don't. Regardless, how do you escape?

If there isn't a good backup means of escape, then MMMs might backfire and become an extremely deadly trap.

1) You can plane shift or gate out.

2) Does Dimensional Lock stop someone from another plane from entering?? I thought it only stopped beings in the area of the spell from leaving.

 

[Marshall Gatten]

1) You can plane shift or gate out.

2) Does Dimensional Lock stop someone from another plane from entering?? I thought it only stopped beings in the area of the spell from leaving.

1. True. My brain was still stuck on the point upthread about Plane Shift not working in relation to the Mansion, but that's obviously only a one-way problem. Still, Plane Shift will land you 5d100 miles from where you went in which could be a major inconvenience. Gate is a better option, but a character unaware of why the Mansion's door won't open might try to use Gate to gate into the room they originally left - which would fail and the spell would fizzle. That's bad news if you only have it prepared once.

2. From the SRD spell description on Dimensional Lock: "Once dimensional lock is in place, extradimensional travel into or out of the area is not possible."

In light of #1, I'm thinking Dimensional Lock makes a very deadly but solvable trap for a user of MMM.

 

[Loren Pechtel]

1. True. My brain was still stuck on the point upthread about Plane Shift not working in relation to the Mansion, but that's obviously only a one-way problem. Still, Plane Shift will land you 5d100 miles from where you went in which could be a major inconvenience. Gate is a better option, but a character unaware of why the Mansion's door won't open might try to use Gate to gate into the room they originally left - which would fail and the spell would fizzle. That's bad news if you only have it prepared once.

2. From the SRD spell description on Dimensional Lock: "Once dimensional lock is in place, extradimensional travel into or out of the area is not possible."

In light of #1, I'm thinking Dimensional Lock makes a very deadly but solvable trap for a user of MMM.

I never realized it was two-way. Yeah, that's nasty although I would be inclined to rule that you can't exit but you're deposited back there anyway when the spell runs out.