Does Astral Projection spell fail if cast while on the Elemental Planes or Material Echo Planes (Shadowfell, Feywild)?

Further to the question: Can there be portals in the Astral Plane that lead to the Elemental Planes , I wanted to ask does Astral Projection spell fail if cast while on the Elemental Planes or Material Echo Planes (Shadowfell, Feywild)?

According to the Etherealness spell (PHB p238) :

This spell has no effect if you cast it while you are on the Ethereal Plane or a plane that doesn’t border it, such as one of the Outer Planes.

According to the Astral Projection spell (PHB 215):

You and up to eight willing creatures within range project your astral bodies into the Astral Plane (the spell fails and casting is wasted if you are already on that plane).

And later in the same spell description:

Your astral form can freely travel through the Astral Plane and can pass through portals there to any other plane.

However, according to DMG in the description of relevant planar travel spells (DMG pg 46) it indicates the following :

And the astral projection spell lets adventurers project themselves into the Astral Plane and from there travel to the Outer Planes.

Accordingly, for both RAW and RAI, does Astral Projection spell fail if cast while on the Elemental Planes or Material Echo Planes (Shadowfell, Feywild)?

Will loot you find on the astral plane while using astral projection remain when you leave it?

While under the effect of astral projection you have an astral body which has the following rules:

Your astral body resembles your mortal form in almost every way, replicating your game statistics and possessions.

I don’t think that you keep stuff if you pick it normally because the following lines (but please correct me if I’m wrong).

Any damage or other effects that apply to it have no effect on your physical body, nor do they persist when you return to it.

It doesn’t specifically say that you cannot pick up loot and take it with you, but it differentiates the astral form from the physical form in a way that they are in no way connected (except the cord).

But, my possessions are being replicated, also my bag of holding. If I pick something up in the astral plane and put it into my bag of holding, will it remain in there when I return to my physical body?

Will the Astral Projection spell end upon entering an Outer Plane?

The astral projection spell states:

If you enter a new plane or return to the plane you were on when casting this spell, your body and possessions are transported along the silver cord, allowing you to re-enter your body as you enter the new plane. Your astral form is a separate incarnation. Any damage or other effects that apply to it have no effect on your physical body, nor do they persist when you return to it.

The highlighted text seems to suggest that, when you enter a new plane via astral projection, your body is transported there as well and you may re-enter your body. This suggests you have lost your astral form and are now physical.

However, DMG 47 implies something different. This section talks about the astral projection spell for the purposes of traveling in the Astral Plane.

Astral Projection

Since the Outer Planes are as much spiritual states of being as they are physical places, this allows a character to manifest in an Outer Plane as if he or she had physically traveled there, but as in a dream.

It further goes on to saying that high level adventurers will often prefer to travel to the Outer Planes via astral projection because dying in this form doesn’t mean “real” death.

So which is the right interpretation? Does astral projection put you back in your real body when entering an Outer Plane, thus ending the spell, or do you remain an astral projection?

Can you avoid the stress penalty of Wish by using Astral Projection?

The wish spell is likely the most powerful and risky spells in Dungeons and Dragons. However, using it to do anything other that duplicate spells carries stress (and potentially losing the spell forever). Below I have quoted the relevant information:

The stress of casting this spell to produce any effect other than duplicating another spell weakens you. After enduring that stress, each time you cast a spell until you finish a long rest, you take 1d10 necrotic damage per level of that spell. This damage can’t be reduced or prevented in any way. In addition, your Strength drops to 3, if it isn’t 3 or lower already, for 2d4 days. For each of those days that you spend resting and doing nothing more than light activity, your remaining recovery time decreases by 2 days. Finally, there is a 33 percent chance that you are unable to cast wish ever again if you suffer this stress.

However, I want do know if these risks carry over to your mortal form, if you were under the effects of astral projection. Below I have quoted the relevant information:

Your astral body resembles your mortal form in almost every way, replicating your game statistics and possessions.

Your astral form is a separate incarnation. Any damage or other effects that apply to it have no effect on your physical body, nor do they persist when you return to it.

So would casting wish while under astral projection subject your body to stress and possibility of losing the spell wish, after astral projection has ended?

When The Undead warlock (UA) uses their Spirit Projection ability, do their spirit and body share a single pool of hitpoints?

The Undead warlock patron can be found here at DnDBeyond or here direct from Wizards of the Coast.

The subclass is freely available playtest content, so I will reproduce the feature here:

Spirit Projection

14th-level Undead feature

Your body is now simply a vessel for your spirit. As an action, you can project your spirit from your body. The body you leave behind is unconscious and in a state of suspended animation.

Your spirit can remain outside your body for up to 1 hour or until your concentration is broken (as if concentrating on a spell). When your projection ends, your spirit returns to your body or your body magically teleports to your spirit’s space (your choice).

While projecting your spirit, you gain the following benefits:

  • Your spirit and body gain resistance to bludgeoning, piercing, and slashing damage.
  • When you cast a spell of the conjuration or necromancy school, the spell doesn’t require verbal, somatic, or material components that lack a gold cost.
  • You have a flying speed equal to your walking speed and can hover. You can move through creatures and objects as if they were difficult terrain, but you take 1d10 force damage if you end your turn inside a creature or an object.
  • While you are using your Form of Dread, once during each of your turns when you deal necrotic damage to a creature, you regain hit points equal to half the amount of necrotic damage dealt.

Once you use this feature, you can’t do so again until you finish a long rest.

This class feature speaks of you and your body as though they are distinct entities in some sense. It seems clear that when the feature says "you" it is referring to "your spirit", and refers to your body as "your body" or "the body".

In this answer, Ben Barden briefly analyzes this feature and makes the assertion:

Nothing is said about funny things happening with HP, so presumably it’s all coming out of the same HP pool. Nothing is said about effects, so, by default, anything that hit either the person or the spirit would affect the whole. So… basically, they’re both a creature, but they’re both the same creature, who now happens to have two locations they can be targeted from.

I’d like to see a more detailed analysis of this feature so that we do not have to say "presumably" as Ben says in their analysis.

Do your spirit and your body share a single pool of hitpoints while using the Spirit Projection feature?

What happens if your body enters astral plane while under astral projection?

If a creature is under astral projection and their body is transported to astral plane, for instance because they got swallowed by the 2x bag of holding combo, what will happen?

Does the astral projection instantly end?
Does the astral projection get suspended until the body gets out the plane?
Does the creature get back to their original body in the astral plane when the spell ends?


Background:

Crawford tweets

In #DnD, the exceptional trumps the general. (No longer being a valid target trumps condition carryover.)

By entering astral plane, the creature would no longer be valid as the target of the spell (because astral projection specifically says so if the caster is on the astral plane), so I thought it will fail.

Fishbowl effect correction in raycasting engine suggestions (pseudo 3d projection)

I’m writing a simple raycaster in golang and I have some problems understanding perspective correction. The code is simple, the main rendering loop is this:

    curVector := playerVector.NewRotated(-curFov / 2)     rotateStep := curFov / float64(screen.Width()) // Angles per screen row     // Traverse each row of our screen, cast a ray and render it to screen buffer     for i := 0; i <= screen.Width(); i++ {         curVector.Rotate(rotateStep)          hit, distance, tile, tileP := rayCast(curX, curY, curVector, viewDistance)          if hit {             // distToHeight is basically linear (screen.Height()/distance)             drawTexturedWallColumn(screen, tile, i, distToHeight(distance, screen.Height()), tileP) // Project walls on screen         }         // drawSpritesColumn(screen, i, curVector, distance) // Project sprites on screen     } 

So I just cast rays with even angle intervals and get this fishbowl effect: enter image description here

So, I understand that the problem is with angle intervals and sphere projected rays with the same length. I found this question How can I correct an unwanted fisheye effect when drawing a scene with raycasting? and tried to implement the same logic:

leftVector := playerVector.NewRotated(90)     // Traverse each row of our screen, cast a ray and render it to screen buffer     for i := 0; i <= screen.Width(); i++ {         progress := float64(i)/float64(screen.Width()) - 0.5 // -0.5 to 0.5         stepX := (playerVector.X + progress*(leftVector.X*2)) // *2 to make 90 FOV         stepY := (playerVector.Y + progress*(leftVector.Y*2))         curVector := Vector{X: stepX, Y: stepY}          hit, distance, tile, tileP := rayCast(curX, curY, curVector, viewDistance)          if hit {             // distToHeight is basically linear (screen.Height()/distance)             drawTexturedWallColumn(screen, tile, i, distToHeight(distance, screen.Height()), tileP) // Project walls on screen         }         // drawSpritesColumn(screen, i, curVector, distance) // Project sprites on screen     } 

But the result is almost the same (FOV variable is not used here but it’s around 90, it’s not important at the moment). The difference is that this one has a more “linear” fishbowl effect because of evenly spaced intervals (progress variable): enter image description here

So, I don’t know how to fix this, I also tried to use perpendicular distance (distance*cos).

How do i get the Mollweide projection of a sphere?

I have defined three angular functions

F1[\[Theta]_,\[Phi]_] := (1/2) (1 + Cos[\[Theta]] Cos[\[Theta]]) Cos[2\[Phi]] F2[\[Theta]_,\[Phi]_] := -Cos[\[Theta]] Sin[2\[Phi]] F3[\[Theta]_,\[Phi]_] := F1[\[Theta],\[Phi]]^2 + F2[\[Theta],\[Phi]]^2 

So I can “project” F3[\[Theta], \[Phi]] on a sphere in the following way

SphericalPlot3D[1,{\[Theta],0,\[Pi]}, {\[Phi],0,2\[Pi]}, ColorFunction -> Function[{x,y,z, \[Theta],\[Phi],r}, ColorData["Rainbow"][F3[\[Theta],\[Phi]]]], ColorFunctionScaling -> False, Mesh -> True, Boxed -> True,  Axes -> True, AxesLabel -> {x, y, z}, PlotPoints -> 100, PlotLegends -> BarLegend["Rainbow"]] 

and use the function to properly color the sphere. Is there a way to do the same thing using a Mollweide projection instead of a sphere?

Does Astral Projection makes a vampire even more vulnerable or harder to kill?

A vampire still have a soul (spirit) in 3.5 as far as I know so since Astral projection states:¸

If the cord is broken, you are killed, astrally and physically

Dying ”physically” or having it’s body destroyed only forces the vampire to go to mist form and go into it’s resting place.

Being killed ”astrally” just mean your new form ”died” and you normally return to your physical body, if the silvery cord is severed then even your material body dies, but that does not affect the vampire. (I might be wrong here)

As far as I understand, it would be clever for a vampire to be even more careful and only go out in his astral form (wich is not exclusive to the Astral plane, even if you are transported there, you can come back with your astral form in the material plane if I remember correctly from a post I saw). His material body would be not too far from it’s resting place, in an extremely secure area, so if it dies, it would just be in his coffin and regenerate. (a fortress with a lot of adamantium doors to break etc. before reaching one of it’s many resting place in a demi-plane so good luck reaching it in 1 hour ;))