Can Plane Shift be used to transport from mordenkainen’s magnificent mansion to the same plane the mansion was created?

The text of Mordenkainen’s Magnificent Mansion (mmm) states:

You conjure an extradimensional dwelling in range that lasts for the Duration.

Plane Shift states:

You and up to eight willing creatures who link hands in a circle are transported to a different plane of existence.

Can a party plane shift from the mansion to the same plane they where in when they created the mansion? i.e. they create the mansion in the material plane, go into the mansion and then plane shift to a new location in the material plane?

Can the Necromancy wizard’s Command Undead feature be used on the Nightwalker from Mordenkainen’s Tome of Foes?

The School of Necromancy wizard has the Command Undead feature (PHB, p. 119):

Starting at 14th level, you can use magic to bring undead under your control, even those created by other wizards. As an action, you can choose one undead that you can see within 60 feet of you. That creature must make a Charisma saving throw against your wizard spell save DC. If it succeeds, you can’t use this feature on it again. If it fails, it becomes friendly to you and obeys your commands until you use this feature again.

Intelligent undead are harder to control in this way. If the target has an Intelligence of 8 or higher, it has advantage on the saving throw. If it fails the saving throw and has an Intelligence of 12 or higher, it can repeat the saving throw at the end of every hour until it succeeds and breaks free.

The Nightwalker from Mordenkainen’s Tome of Foes (p. 216) has 8 charisma, 6 intelligence and a CR of 20.

Isn’t it a bit crazy? Outside of simply not putting this thing in the game if you have a necromancy wizard in it, what else can happen (or can the DM do) that is gonna prevent the game from breaking?

Does Mordenkainen’s Private Sanctum prevent me from opening a Portable Hole?

Mordenkainen’s Private Sanctum says that

planar travel is blocked within the warded area

and the portable hole’s description states that

the cylindrical space within the hole exists on a different plane.

Does this mean that portable holes’ contents can’t be accessed within a private sanctum?

What happens to items left in Mordenkainen’s Magnificent Mansion?

Recently, the question arose as to what happens when you leave objects you own in Mordenkainen’s Magnificent Mansion. The spell description does not specify if you always conjure the same Mansion, or if it is a different one. So what happens if I leave something like my magic short sword in it? Or even a mundane item, like my mundane pottery?

The spell says that creatures are expelled when the spell ends, and it says what happens to things from the mansion that you want to take outside, but there is nothing about items taken into the mansion. Is there any information in the rules, somewhere?

Can Mordenkainen’s Faithful Hound be made mobile by casting it on a mobile surface?

The description of the Mordenkainen’s faithful hound spell says, in part:

You conjure a phantom watchdog in an unoccupied space that you can see within range, where it remains for the duration, until you dismiss it as an action, or until you move more than 100 feet away from it.

If I were to cast Mordenkainen’s faithful hound to conjure the hound on a wagon, or on Tenser’s floating disk, would the hound then be able to follow me around and remain active for it’s 8 hour duration?

Is the “Bone of Animation” in Mordenkainen’s Tome of Marvelous Magic unbalanced?

I’m running Descent into Avernus.

In a session 0 for one my PCs, they acquired a Bone of Animation, which is an item in Mordenkainen’s Tome of Marvelous Magic.

(This is a pretty great list of magical items on dmsguild: https://www.dmsguild.com/product/291001/Mordenkainens-Tome-of-Marvelous-Magic)

BONE OF ANIMATION

Wondrous item, uncommon (requires attunement)

This item appears to be a regular human upper arm bone. While holding the bone you can use an action to speak the command word and turn the bone into a skeleton. The skeleton reverts to bone form after 1 hour or when it drops to 0 hit points.

The skeleton is friendly to you and your companions for the duration. Roll initiative for the skeleton, which has its own turns. It obeys any verbal commands that you issue to it (no action required by you). If you don’t issue any commands to the skeleton, it defends itself from hostile creatures but otherwise takes no actions.

Once the bone is used, it can’t be used again until the next dawn.

So far, so good. This is a pretty cool item.

We’re now approaching level 5, and my wizard is super excited to use Animate Dead when he levels:

This spell creates an undead servant. … On each of your turns, you can use a bonus action to mentally command any creature you made with this spell if the creature is within 60 feet of you (if you control multiple creatures, you can command any or all of them at the same time, issuing the same command to each one). You decide what action the creature will take and where it will move during its next turn, or you can issue a general command, such as to guard a particular chamber or corridor. If you issue no commands, the creature only defends itself against hostile creatures… The creature is under your control for 24 hours, after which it stops obeying any command you’ve given it. To maintain control of the creature for another 24 hours, you must cast this spell on the creature again before the current 24-hour period ends. This use of the spell reasserts your control over up to four creatures you have animated with this spell, rather than animating a new one.

By comparison to this, the Bone of Animation seems overpowered:

  • It does not require a spell slot to use
  • You can issue verbal commands without using an action

Whereas for Animate Dead:

  • You must expend a spell slot
  • You have to use a bonus action to command the creatures

The only downsides of the Bone is that you can use it only once per day, and the skeleton lasts for at most one hour. But in a typical adventuring day, there is probably one combat encounter that would require pulling out all the stops — so neither of these downsides seems that impactful.

I do understand that Animate Dead scales well, and at higher casting levels you can start to control groups of undead. But it seems very off to me that Animate Dead requires a bonus action to command, whereas the Bone does not. Every similar item in the Tome of Marvelous Magic is the same, so I assume it was a deliberate decision by authors.

The question I need an answer to:

I’m thinking of editing the Bone so that it also requires a bonus action to command. Without this I anticipate my wizard asking me why he has to expend a bonus action when my other PC does not.

Does this modification negatively impact game play or materially change the balance implications for this item?

Are the Tiefling subraces from Mordenkainen’s Tome of Foes specific to a particular campaign set?

Are the Tiefling subraces from Mordenkainen’s Tome of Foes specific to a particular campaign set?

In Mordenkainen’s Tome of Foes (MTF) there is a section on Tiefling Subraces (p.21), which elaborates on how the information about a Tiefling’s ability score increase and the Infernal Legacy contained in the Player’s Handbook relates to Asmodeus. Let’s say the “default Tiefling” prior to MTF.

Under Tieflings Subraces there is a variety of Subrace Traits for e.g. Tieflings associated with Baalzebul or Fierna.

It says this is a DM’s option to include other Tiefling subraces, but I was wondering: Is this intended specific to a particular Campaign Set, or it’s meant to be a global change?

Does Mordenkainen’s Private Sanctum prevent Devil’s Sight from working?

I could compare it to this question about whether the Devil’s Sight invocation allows one to see into Hunger of Hadar, but that question has an easy answer, due to the ‘blinded’ condition it affects the person inside with. However, the spell Mordenkainen’s Private Sanctum does not give the ‘blinded’ effect- it merely states that, in one of its properties:

The barrier of the warded area appears dark and foggy, preventing vision (including darkvision) through it.