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Renduaz
2018-10-03, 12:15 PM
I've recently been having an interesting argument somewhere about the RAW of Leomund's Tiny Hut, specifically pertaining to the following stipulations in the description:

>" A 10-foot-radius immobile dome of force springs into existence around and above you and remains stationary for the duration."

The argument begun based on what would happen ( And some of you might know where this is coming from ) if someone were to cast the Tiny Hut on a moving ship. I said that based on the first, primary definition of immobile in particular ( incapable of moving or being moved. ), even if were to make leeway toward 'stationary', what would happen at best is that the caster and the moving ship would simply sail past the boundaries of the dome of force that sprang up around him in a few seconds, at which point the spell would dissipate, or at worst ( And this is even more accurate in my opinion ) - The hut would completely break the ship apart as it's rear section, which wasn't inside the 10 foot radius at the time of casting, would get completely raked against the hut's hemisphere in a tug-of-war game between the section of the ship that was inside the AOE that is still trying to sail forward and the area which wasn't, now being barred by the hut. Imagine a titan just driving down a wedge into the middle, basically.

The opposition retorted that I'm wrong and that it is 'implicitly understood' that the hut is "anchored" to some point of reference like a ground or surface. I of course told them that not only is it written nowhere in the spell itself, but there are spells which do refer to a ground or surface ( I.E Tenser's Disk ), but this one explicitly does not. You can cast it in the air or in space or anywhere you want to and it springs into existence around you. ( And yes, it does have a floor (https://twitter.com/jeremyecrawford/status/823774362293542912?lang=en) )

So then they asked if that means whenever anyone casts the hut on the ground in a planet which is rotating or orbiting a sun, whether the hut gets instantly jettisoned away from him as a completely immobile ( relative to the 3D space it occupies ) magical force dome that is not affected by gravity and is incapable of moving or being moved. I responded that if your fantasy D&D planet employs real earth physics ( which ****s up A LOT of spells, Teleportation for instance ), then yes, by RAW that is exactly what would happen, no matter how outlandish it sounds. The hut will only remain around you on a crystal sphere/planet that does not abide by those laws. ( I.E does not rotate, and either the sun orbits it or else some kind of magic/god is responsible for day night cycles )

So a major argument ensued, and I proceeded to ask - If we're going to rule that the hut can simply be carried by a moving ship, despite being immobile, which goes against everything that the spell is trying to prevent, namely that you won't be able to just bring it with you wherever you need it, then does that mean if I cast it while riding a horse, it's now moving with me on the horse? If I cast it while holding a stick, does the stick work as a frame reference? What happens to the hut on the moving ship if the ship gets destroyed? If a chunk of wood from the deck it was cast upon survives and floats on the water, does the hut keep moving along with it? If the hut now uses the sea as references, does it it move with the waves or does it, arbitrarily, not move at all? If a giant asteroid destroys the planet you're on, what happens with the hut and the caster inside it? Since it apparently responds to gravitational pull, does it begin to orbit the sun or spin around with the debris?

Basically, in order to justify ascribing "implicit understandings" to immobility and straying from the explicit RAW, you end up in a spiral of infinite, arbitrary, and probably contradictory adjudications in a bid for consistency, and none of it based on the actual spell. So as far as I'm concerned, the hut is exactly as I read it - an immobile dome of force with no anchors or surfaces or grounds whatsoever, except the space on which it was imposed. Even if that means that yes, if your D&D world is a perfect replica of earth, then you do get spirited away from it every single time you try to cast it, with the only fix being to make your physics fit RAW instead of making RAW fit our own universe's physics.

But maybe someone could offer a better insight.

Unoriginal
2018-10-03, 12:16 PM
If you are standing still on a moving ship, without moving an inch yourself, are you immobile?

MaxWilson
2018-10-03, 12:20 PM
So then they asked if that means whenever anyone casts the hut on the ground in a planet which is rotating or orbiting a sun, whether the hut gets instantly jettisoned away from him as a completely immobile ( relative to the 3D space it occupies ) magical force dome that is not affected by gravity and is incapable of moving or being moved. I responded that if your fantasy D&D planet employs real earth physics ( which ****s up A LOT of spells, Teleportation for instance ), then yes, by RAW that is exactly what would happen, no matter how outlandish it sounds. The hut will only remain around you on a crystal sphere/planet that does not abide by those laws. ( I.E does not rotate, and either the sun orbits it or else some kind of magic/god is responsible for day night cycles )

That doesn't follow. In real life, there is no preferred frame of reference[1], so you can define a reference frame in which objects resting on the Earth are immobile, or a reference frame in which objects resting on the Earth are moving thousands of miles per hour around the sun, and it doesn't matter which one you use because they both give the same predictions in every situation.

But if you're trying to make 5E physics work, you can just say the dome is immobile w/rt the center of mass of the local planetary body (and maybe it doesn't work at all outside the gravitational field of a planetary body). And that's a perfectly locally-valid reference frame.

Anyway, "real earth physics" has nothing to say about how Leomund's Tiny Hut should operate. Real earth physics has no problem if you just use a sensible definition of "immobile". Real earth physics is not opinionated about reference frames.

[1] That we know of. Obviously, if somebody discovered a phenomenon which ONLY works w/rt some specific reference frame, all of that would go out the window and we'd have to re-invent much of modern astrophysics to account for the new phenomenon.

Renduaz
2018-10-03, 12:29 PM
If you are standing still on a moving ship, without moving an inch yourself, are you immobile?

Nope. You are in fact both moving and being moved, or in other words, the direct opposite of the definition. Do people use the word 'immobile' less rigorously in daily life? Of course, you're moving every time you breath too, right? But since it's a dome of magical force that we're speaking of here which can stop anything in it's path, then we need a *literal* definition. And this is the only one which the spell gives us.


That doesn't follow. In real life, there is no preferred frame of reference[1], so you can define a reference frame in which objects resting on the Earth are immobile, or a reference frame in which objects resting on the Earth are moving thousands of miles per hour around the sun, and it doesn't matter which one you use because they both give the same predictions in every situation.

But if you're trying to make 5E physics work, you can just say the dome is immobile w/rt the center of mass of the local planetary body (and maybe it doesn't work at all outside the gravitational field of a planetary body). And that's a perfectly locally-valid reference frame.

So would it or wouldn't it enable the casting on a moving ship, or moving horse, or the back of a Goliath that you're being carried around by while casting it? Also, while it might be a perfectly valid reference frame, it won't be perfectly valid RAW - There are no restrictions on casting the hut in outer space, in a plane, in the Astral Sea, or anywhere else.


Anyway, "real earth physics" has nothing to say about how Leomund's Tiny Hut should operate. Real earth physics has no problem if you just use a sensible definition of "immobile". Real earth physics is not opinionated about reference frames.

[1] That we know of. Obviously, if somebody discovered a phenomenon which ONLY works w/rt some specific reference frame, all of that would go out the window and we'd have to re-invent much of modern astrophysics to account for the new phenomenon.

And what's the sensible definition?

DMThac0
2018-10-03, 12:44 PM
So would it or wouldn't it enable the casting on a moving ship, or moving horse, or the back of a Goliath that you're being carried around by while casting it? Also, while it might be a perfectly valid reference frame, it won't be perfectly valid RAW - There are no restrictions on casting the hut in outer space, in a plane, in the Astral Sea, or anywhere else.

is answered by this:


Nope. You are in fact both moving and being moved, or in other words, the direct opposite of the definition. Do people use the word 'immobile' less rigorously in daily life? Of course, you're moving every time you breath too, right? But since it's a dome of magical force that we're speaking of here which can stop anything in it's path, then we need a *literal* definition. And this is the only one which the spell gives us.

If we follow this logic then you would never be able to cast Leomond's Tiny Hut ever. The planets are moving in an orbital and rotational direction, you are standing on the planet, thus you are both moving and being moved. The only way that wouldn't be true is if your planet is the center of the universe, with no orbit and no rotation, and such a thing would "realistically" cause issues with gravity and other physics.

If, however, you pause for a moment and consider that larger bodies may be able to carry an object and that object is considered immobile then we can move forward with this discussion. An object reaching a certain size, mainly something able to carry Leomond's Tiny Hut, without causing impediment could then be assumed to work.

-Cast it on a wagon that is slightly bigger than the hut, 12' by 14' to accommodate entering and exiting the hut; No, as the object is barely considered "Large" by the game's standards.
-Cast it on a ship which has a deck that is 18' by 60'; yes as the object is multiple size categories larger and considered able to carry/haul/house cargo and people.

There is something to be said about using common sense when asking these questions rather than trying to argue something which, if you were to search for it, has been run into the ground multiple times already.

Renduaz
2018-10-03, 12:55 PM
is answered by this:



If we follow this logic then you would never be able to cast Leomond's Tiny Hut ever. The planets are pulled by a gravitational force, you are standing on the planet, thus you are both moving and being moved.

You're talking about our own universe's physics. D&D Physics do not necessarily align, and gravitational exertion alone will not suffice to make the hut un-usable anyway. The hut is evidently not affected by gravity, hence why it doesn't fall down when you cast it in the air, much like Wall of Force ( which can be explicitly free-floating ). You can still use the hut or the wall though. All that matters is whether the "planet" ( prime material ) is moving or not.


If, however, you pause for a moment and consider that larger bodies may be able to carry an object and that object is considered immobile then we can move forward with this discussion. An object reaching a certain size, mainly something able to carry Leomond's Tiny Hut, without causing impediment could then be assumed to work.

-Cast it on a wagon that is slightly bigger than the hut, 12' by 14' to accommodate entering and exiting the hut; No, as the object is barely considered "Large" by the game's standards.
-Cast it on a ship which has a deck that is 18' by 60'; yes as the object is multiple size categories larger and considered able to carry/haul/house cargo and people.

There is something to be said about using common sense when asking these questions rather than trying to argue something which, if you were to search for it, has been run into the ground multiple times already.

Anything at all can 'carry' the hut because it's self-suspended, has no weight and requires no support. You could """"carry"""" the hut on the tip of a spear that's been wedged into the earth if you wanted to. The only thing you're saying right now is basically that you'd only allow the casting of the hut as long as it is above some object which is bigger in volume or diameter than it, which is not only arbitrary but actually makes no common sense at all.

If I take an 18' by 60' blanket and cast the hut while standing on it, apparently the hut will now start getting dragged along with the blanket when I start pulling it. If there's a hole in the blanket, is it still the blanket? What happens if there's a hole in the deck? Does the hut fall? Does it finally stay behind? None of this is common sense as soon as you start really thinking about it. Why? because of trying to turn the hut into something that it's not. The hut is an immobile dome of force which has no weight and doesn't fall down when a surface is whisked away from it. It's not an actual straw hut.

If we want to violate the strict definition here, then you'd have to really own it. Just say "The hut can be cast wherever I think that it should be available to players, and move whenever I think it should move, and that's the only rule." - Then you'd actually be able to exercise common sense. No really, the spell can only make sense either by treating the word immobile like gospel, or else by making judgement calls about what a 'reasonable' anchor is based on case-specific personal taste and DM'ing style. ( Which goes into Ruling territory )

DMThac0
2018-10-03, 01:07 PM
https://www.sageadvice.eu/2016/06/26/could-i-cast-tiny-hut-in-the-middle-of-ocean-or-it-needs-a-floor/

https://www.sageadvice.eu/2017/05/20/would-leomunds-tiny-hut-be-able-to-be-cast-and-then-stay-on-an-ancient-dragon/

It seems that you are intent on finding a way to say that you cannot cast the spell. I am not a fan of quoting Sage Advice, but I figure that the only argument you'll take as valid will be from the guys at WotC...

Nifft
2018-10-03, 01:11 PM
I'd probably rule that the Tiny Hut requires a solid, stationary surface in which to ground itself.

The ship and the ocean would not qualify unless the ocean was becalmed and the ship was (relatively) stationary.

Renduaz
2018-10-03, 01:13 PM
https://www.sageadvice.eu/2016/06/26/could-i-cast-tiny-hut-in-the-middle-of-ocean-or-it-needs-a-floor/

https://www.sageadvice.eu/2017/05/20/would-leomunds-tiny-hut-be-able-to-be-cast-and-then-stay-on-an-ancient-dragon/

It seems that you are intent on finding a way to say that you cannot cast the spell. I am not a fan of quoting Sage Advice, but I figure that the only argument you'll take as valid will be from the guys as WotC...

Mike Mearl's answers are not official rules for a reason. Only Crawford is ( And Crawford contradicted Mearl's answers on several occasions ). Now, the second link is an interesting dilemma - Did Crawford imply that the hut would slide off because the force dome has friction, weight, and would be anchored to the dragon's back, or that it would slide off because it would just stay behind as soon as the Dragon flew away from it?

I don't know, maybe it was the former, but the former does not match with the spell's description.

MaxWilson
2018-10-03, 01:14 PM
So would it or wouldn't it enable the casting on a moving ship, or moving horse, or the back of a Goliath that you're being carried around by while casting it?

Are you asking me as DM? If so, my answer is, "It's immobile with respect to the local planetary body. If you cast it on a moving ship you're inviting the ship and the hut to smash themselves against each other, probably damaging the ship and destroying the hut."


Also, while it might be a perfectly valid reference frame, it won't be perfectly valid RAW - There are no restrictions on casting the hut in outer space, in a plane, in the Astral Sea, or anywhere else.

If you want to define a reference frame that works in wildspace/Astral Sea/etc. you are free to do that, as DM. One logical way to do it would be to say, "When cast outside of a planetary gravitational field, it is immobile with respect to the closest crystal sphere."


And what's the sensible definition?

I gave you one just now. You're free to use a different one. The point is that it's not "THE sensible definition", it's "a sensible definition." You can pick whatever sensible definition you want and real-life physics doesn't care.

Renduaz
2018-10-03, 01:18 PM
Are you asking me as DM? If so, my answer is, "It's immobile with respect to the local planetary body. If you cast it on a moving ship you're inviting the ship and the hut to smash themselves against each other, probably damaging the ship and destroying the hut."



If you want to define a reference frame that works in wildspace/Astral Sea/etc. you are free to do that, as DM. One logical way to do it would be to say, "When cast outside of a planetary gravitational field, it is immobile with respect to the closest crystal sphere."

Well, that's practical as a ruling. But personally I would stick with "The Hut is immobile, period. It cannot move or be moved, by anything at all". Only because it is the unadulterated wording that requires no further arbitrary decisions on my part. Still though, using the local planetary body does make for much less potential random decisions as opposed to the mess which ensues by allowing the hut to travel on ships simply because they happened to spring into existence above a deck.

Tanarii
2018-10-03, 01:19 PM
The answer to this question is for the DM to another question:
Is the player trying to be a rules-abusing muchkin or a savvy tactical innovater?

If the former, disallow the frame of reference you find abusive.

If the latter, congratulate the player on finding an innovative use of the frame of reference.

Personally I know which side of the line I put the argument that spell wouldn't work on a planet rotating through space.

A moving ship could fall either way for either frame of reference.

Again, IMO a moving wagon moving the hut with it is pretty obvious where it belongs, in my book.

Other DMs will have their own dividing lines. Always is when it comes to "physics interactions extensions of spells.

iTreeby
2018-10-03, 01:38 PM
Have boats be recognized as their own frame of reference because the ocean gods decided that the game is more fun when playable.

tieren
2018-10-03, 01:38 PM
We use as a frame of reference the map. If it is big enough to need a map to describe you can cast Tiny Hut relative to it.

If its a small fishing boat probably not. If its 4 story galleon with dozens of rooms, we would allow it for a long rest in a cargo hold.

It would have to be a massive wagon for that to ever work (are the rolling Ziggurats still a thing?)

Common sense prevails.

DrowPiratRobrts
2018-10-03, 01:49 PM
1) I want to rule with the hut moving with the ship, but I won't because I like the idea of someone casting it and then the ship coming to a halt and remaining anchored for 8 hours.

2) Speed is relative. If you put a ball on the ground it's immobile, but only because it's moving with the same velocity and rotation as everything else on earth. It's relative speed/movement in the system is nonexistent, but it is actually hurtling through space. This is why if you're in a car holding a ball and you throw it in the air, it begins to decelerate. It's no longer moving with the system because no force is pushing it. If you had a tall enough car you could throw it straight up and watch it eventually hit the back of the car.

3) I want to rule with the hut making the ship stay anchored since the spell isn't centered on a point, but I actually like the idea better that the ship is able to sufficiently contain the hut as someone described above. This is obviously not the case for a horse and probably wouldn't be for a wagon either with the possible exception that it's completely enclosed like a tractor trailer.

4) Just to drop a bomb really quick...what about oxygen? It's matter. It's an object. You wouldn't have enough oxygen inside the hut for 8 hours with a full party, so can oxygen pass through the walls? Though this is slightly different than the ship, it provides a similar train of thought. The atmosphere is a much larger system that actually contains the hut, so it is able to pass through. Also so you don't have your players sleep in a death trap and never wake up. Sometimes we have to bend the RAW a little bit to arrive at a logical conclusion.

Sigreid
2018-10-03, 02:29 PM
I'm not that concerned with RAW or SA. My ruling would be that it would move with the ship. The line would be that it moves with a reference large and solid enough to be the ground for all intents and purposes. So a large sailing ship would work, a cloak, wagon or rowboat would not. I would probably draw the line at somewhere around the size of an inn.

Ganymede
2018-10-03, 02:35 PM
Leomund is locked in place in reference to whatever battle map you are using.

Problem solved.

tieren
2018-10-03, 02:54 PM
2) Speed is relative. If you put a ball on the ground it's immobile, but only because it's moving with the same velocity and rotation as everything else on earth. It's relative speed/movement in the system is nonexistent, but it is actually hurtling through space. This is why if you're in a car holding a ball and you throw it in the air, it begins to rapidly decelerate. It's no longer moving with the system because no force is pushing it. If you had a tall enough car you could throw it straight up and watch it eventually hit the back of the car.


4) Just to drop a bomb really quick...what about oxygen? It's matter. It's an object. You wouldn't have enough oxygen inside the hut for 8 hours with a full party, so can oxygen pass through the walls? Though this is slightly different than the ship, it provides a similar train of thought. The atmosphere is a much larger system that actually contains the hut, so it is able to pass through. Also so you don't have your players sleep in a death trap and never wake up. Sometimes we have to bend the RAW a little bit to arrive at a logical conclusion.

Tangent, but:

In 2) that is not the way real world physics work. Newton's first law of motion, the ball moving forward with the car at 100 mph would tend to continue moving forward with the car unless acted upon by an outside force (air resistance, etc...) its why a gnat in the car can fly from the back seat to the front seat even though gnats can't fly 100+ mph.

In 4) the answer is magic, the spell text explicitly describes the condition of the atmosphere inside the hut.

DrowPiratRobrts
2018-10-03, 03:34 PM
Tangent, but:

In 2) that is not the way real world physics work. Newton's first law of motion, the ball moving forward with the car at 100 mph would tend to continue moving forward with the car unless acted upon by an outside force (air resistance, etc...) its why a gnat in the car can fly from the back seat to the front seat even though gnats can't fly 100+ mph.

In 4) the answer is magic, the spell text explicitly describes the condition of the atmosphere inside the hut.

2) It is the way real world physics work. I never said the deceleration happens quickly, but it absolutely happens. Ask a physics professor, they can explain it to you better. My friend argued about this with me for a long time as a kid and then in physics our teacher explained it. In layman's terms, basically while the ball is suspended in midair the molecules in the air of the car cannot exert enough force, due to their gaseous form, in order to continue the ball's forward motion. So the ball decelerates it's horizontal motion since it's being pushed with less force and it accelerates toward the ground due to gravity.

4) Fair point, but I was simply using that as an example why you can't take the spell too literally. I don't think the PCs should run out of oxygen and I made that clear.

Gryndle
2018-10-03, 03:40 PM
I've recently been having an interesting argument somewhere about the RAW of Leomund's Tiny Hut, specifically pertaining to the following stipulations in the description:

>" A 10-foot-radius immobile dome of force springs into existence around and above you and remains stationary for the duration."

The argument begun based on what would happen ( And some of you might know where this is coming from ) if someone were to cast the Tiny Hut on a moving ship. I said that based on the first, primary definition of immobile in particular ( incapable of moving or being moved. ), even if were to make leeway toward 'stationary', what would happen at best is that the caster and the moving ship would simply sail past the boundaries of the dome of force that sprang up around him in a few seconds, at which point the spell would dissipate, or at worst ( And this is even more accurate in my opinion ) - The hut would completely break the ship apart as it's rear section, which wasn't inside the 10 foot radius at the time of casting, would get completely raked against the hut's hemisphere in a tug-of-war game between the section of the ship that was inside the AOE that is still trying to sail forward and the area which wasn't, now being barred by the hut. Imagine a titan just driving down a wedge into the middle, basically.

The opposition retorted that I'm wrong and that it is 'implicitly understood' that the hut is "anchored" to some point of reference like a ground or surface. I of course told them that not only is it written nowhere in the spell itself, but there are spells which do refer to a ground or surface ( I.E Tenser's Disk ), but this one explicitly does not. You can cast it in the air or in space or anywhere you want to and it springs into existence around you. ( And yes, it does have a floor (https://twitter.com/jeremyecrawford/status/823774362293542912?lang=en) )

So then they asked if that means whenever anyone casts the hut on the ground in a planet which is rotating or orbiting a sun, whether the hut gets instantly jettisoned away from him as a completely immobile ( relative to the 3D space it occupies ) magical force dome that is not affected by gravity and is incapable of moving or being moved. I responded that if your fantasy D&D planet employs real earth physics ( which ****s up A LOT of spells, Teleportation for instance ), then yes, by RAW that is exactly what would happen, no matter how outlandish it sounds. The hut will only remain around you on a crystal sphere/planet that does not abide by those laws. ( I.E does not rotate, and either the sun orbits it or else some kind of magic/god is responsible for day night cycles )

So a major argument ensued, and I proceeded to ask - If we're going to rule that the hut can simply be carried by a moving ship, despite being immobile, which goes against everything that the spell is trying to prevent, namely that you won't be able to just bring it with you wherever you need it, then does that mean if I cast it while riding a horse, it's now moving with me on the horse? If I cast it while holding a stick, does the stick work as a frame reference? What happens to the hut on the moving ship if the ship gets destroyed? If a chunk of wood from the deck it was cast upon survives and floats on the water, does the hut keep moving along with it? If the hut now uses the sea as references, does it it move with the waves or does it, arbitrarily, not move at all? If a giant asteroid destroys the planet you're on, what happens with the hut and the caster inside it? Since it apparently responds to gravitational pull, does it begin to orbit the sun or spin around with the debris?

Basically, in order to justify ascribing "implicit understandings" to immobility and straying from the explicit RAW, you end up in a spiral of infinite, arbitrary, and probably contradictory adjudications in a bid for consistency, and none of it based on the actual spell. So as far as I'm concerned, the hut is exactly as I read it - an immobile dome of force with no anchors or surfaces or grounds whatsoever, except the space on which it was imposed. Even if that means that yes, if your D&D world is a perfect replica of earth, then you do get spirited away from it every single time you try to cast it, with the only fix being to make your physics fit RAW instead of making RAW fit our own universe's physics.

But maybe someone could offer a better insight.

by your same reasoning it becomes a WMD by the fact that it doesn't move with the planet. when in doubt don't ascribe physics-nullifying powers to a spell that would be above that spell level.

lperkins2
2018-10-03, 03:52 PM
So, the short answer is it's up to the DM.

If the local cosmology uses the Ptolemaic system, then sure, you can say it must be perfectly stationary. You can also always define it as stationary to the largest nearby gravity source. This is a subset of the general question about spell reference frames, which always comes down to the local cosmology. For example, if in the local cosmology, the planet moves roughly similarly to how Earth moves, then teleport, if it does not sync your velocity to the destination reference frame, is basically an instant death sentence if you try to go more than a fairly short distance away. Other affected spells include Gate, Plane Shift, Glyph of Warding, and a large variety of others. There isn't a right answer to the question, but it is a good idea if the answer is consistent across related spells, and matches with the cosmology of the world. Mismatches can generally be weaponized by smart PCs (like casting L'sTH in front of a the mast of a ship cripple it).

KorvinStarmast
2018-10-03, 05:43 PM
Have boats be recognized as their own frame of reference because the ocean gods decided that the game is more fun when playable. If you have ever landed an aircraft on a ship at sea, you will likely agree with me that a ship at sea, while moving as compared to the surface of the planet, is certainly able to be a frame of reference such that I can (and did many times) make a successful landing on it. :smallbiggrin:

To answer the OP's question.

While I appreciate your muse in exploring these kinds of questions, I also think that you are overthinking it.

For example, if the ship is large enough for a large or huge flying creature to land upon without upsetting the stability of the ship, you have a size range to work with in choosing "yes, big enough" for hut or "no, too small" for hut.

Large creature carries one medium creature easily for flying, in D&D 5e pseudophysics.
Manticore, Nightmare, Hippogriff, Pegasus, Giant Vulture, Giant Eagle, Giant Owl, WYvern, Gynosphinx / Androsphinx, Griffon, Efreeti, Djinni, Air Elemental. All Young Dragons. Pit Fiend, Horned Devil. Bone Devil. Vrock. Chimera. The Large Celestials.

A huge creature carries a lot more, up to as many as fit into the hut.
All Adult Dragons. Roc. Some Huge Demons like Balor.

A ship that can handle the huge one landing on the, no worries.
A ship that can just handle the large ones landing without upsetting stability, probably too small.

Somewhere between those two sizes of ship is a nice range of "yes, big enough and stable enough for LTH."

That's one way to look at it.

Alternatively:
LTH is about the same size as a small to medium sized helicopter.
If the ship is about the size of a yacht that can land those helicopters, then it's probably big enough for LTH.

JackOfAllBuilds
2018-10-03, 07:18 PM
Sea sickness and “getting your land-legs” is a thing, dealing with motion and frame of reference. Google MdDS, the continued rocking after finishing a cruise.

On the backs of creatures obviously should not be allowed, but any inanimate vehicle large enough to be considered a building or structure with either/or both multiple floors or rooms. A siege tower is a tower on wheels. I can put a tiny hut on a tower.

(Simplest reasoning: “could I build a hut here?” Deck of a barge: yes. Dragons back: no.)

stoutstien
2018-10-03, 07:50 PM
Other spells to consider with how you rule this
Glyph of ward-
Aoe concealment- fog cloud, silent image, darkness, and so on.
Wall spells-
Teleport circle-

theMycon
2018-10-03, 11:39 PM
2) It is the way real world physics work. I never said the deceleration happens quickly, but it absolutely happens. Ask a physics professor, they can explain it to you better. My friend argued about this with me for a long time as a kid and then in physics our teacher explained it. In layman's terms, basically while the ball is suspended in midair the molecules in the air of the car cannot exert enough force, due to their gaseous form, in order to continue the ball's forward motion. So the ball decelerates it's horizontal motion since it's being pushed with less force and it accelerates toward the ground due to gravity.


Assuming the windows are closed & the AC is off, it is absolutely not. This is very easy to test. Tape a pendulum to the roof inside a car moving at a constant rate*. Or hold a piece of paper by the top. Or however you want to cancel out the force of gravity so you can continue the test indefinitely. You will see the object in question remain stationary relative to the car. If the car's a closed system, there aren't forces acting on its horizontal velocity, so there's no acceleration or deceleration. Like Tieren said, this is a straightforward example Newton's first law of motion.

If your physics teacher actually said something like that, (s)he was wrong in enough ways that they have no business teaching physics. A little bit of wrongness is expected of everyone- teachers are human too, that's why we have different teachers covering overlapping information in different courses- but "the air molecules cannot exert enough force to continue the ball's forward motion" is egregious.

Also, you did say the deceleration happens quickly when you said
it begins to rapidly decelerate.

*Don't drive while experimenting. Both activities deserve your full attention, and there's easier access to open space from the back seat anyway.

Tanarii
2018-10-04, 12:05 AM
and then in physics our teacher explained it.
Either your teacher was wrong, or he was telling you something different from what you thought you were being told. That's not what happens and not how physics works.

If I had to guess, I'd say your teacher was talking about an accelerating vehicle.

DrowPiratRobrts
2018-10-04, 09:02 AM
Assuming the windows are closed & the AC is off, it is absolutely not. This is very easy to test. Tape a pendulum to the roof inside a car moving at a constant rate*. Or hold a piece of paper by the top. Or however you want to cancel out the force of gravity so you can continue the test indefinitely. You will see the object in question remain stationary relative to the car. If the car's a closed system, there aren't forces acting on its horizontal velocity, so there's no acceleration or deceleration. Like Tieren said, this is a straightforward example Newton's first law of motion.

If your physics teacher actually said something like that, (s)he was wrong in enough ways that they have no business teaching physics. A little bit of wrongness is expected of everyone- teachers are human too, that's why we have different teachers covering overlapping information in different courses- but "the air molecules cannot exert enough force to continue the ball's forward motion" is egregious.

Also, you did say the deceleration happens quickly when you said

*Don't drive while experimenting. Both activities deserve your full attention, and there's easier access to open space from the back seat anyway.

Even with the AC off and the windows closed, you're not in a pressurized vacuum. When the AC is off in every car I've been in and you're going 70 mph you can still feel some air coming through the vents.

Not sure why I put the word rapidly there. That was a mistake. I'm not trying to argue that it's a noticeable change to the naked eye. And using a pendulum or holding a piece of paper is different because it's still tied to the system like parasailing or water skiing. My point is, there is actually air resistance even if it's minimal. I agree with what you're saying, but our assumptions about the car were not the same.

Tanarii
2018-10-04, 09:08 AM
That's not how physics works.

Joe the Rat
2018-10-04, 11:27 AM
If you really need to lock things into physics, mobility is always in reference to the local gravity well, which will be the planet. If you are spacefaring, consider researching a variant where you can explicitly fix your point of reference, because if you're in orbit and fussing about absolute motion, you might as well bring in relativity, which messily quashes absolute anything about spacetime.

If you're Spelljamming, you already know about the gravity planes on the vessels, which can serve as an anchor reference.

Me, I take a narrative approach. What is the ship? Yes, it's a vehicle, but as you travel, it is also your immediate (man-made) terrain. It's your point of reference, and random encounters are coming to you as much as you are coming to them. If your vessel is smaller than the hut, then the hut defines the terrain, and renders the vehicle immoble (and likely contained) for the duration. A good way to stretch your legs while piled in a life raft.

DrowPiratRobrts
2018-10-04, 11:40 AM
Leomund is locked in place in reference to whatever battle map you are using.

Problem solved.

Many of us don't use grids/maps to play 5e though, so this is a good solution for some but not universal.

Shining Wrath
2018-10-04, 11:55 AM
This is a classic "rulings, not rules" situation. Where you can and can't put a LTH is up to your DM.

I like to use the "Which ruling can be abused the most - don't take that viewpoint" approach.

If LTH is immobile with respect to things like ships, a wizard could destroy the strongest ship ever built by teleporting into the hold, casting LTH, and then teleporting back out, if there was a strong wind and the ship was under sail.

If LTH is mobile with respect to things like wagons, then armies would use them as tanks.

Therefore, neither of those things work, because it's magic and it doesn't have to make sense. A LTH on the deck of a ship moves with the ship, a LTH on a large wagon slides off. Perhaps the weight of the thing carrying the LTH has to be at least 10 tons. If you can tame a 10-ton dragon, you're probably past the point where LTH is a big advantage in combat anyway.

Also, it's a plausible ruling that the things that were within LTH when it was cast (other than the caster) cannot be separated into two things, one inside the hut and one outside - so firing arrows from within LTH won't work. The archer has to step outside, fire, and then step back inside.

LTH can be used to block narrow passes, or narrow straits. To cast underwater you need Water Breathing in some form, but if cast in a passage only 10' wide, or in water not much greater than 10' deep, it's a nice plug.

xroads
2018-10-04, 11:55 AM
Immobile is a relative term. We can use the term to describe houses in our world, but a flood can certainly change that in a heart-beat.

In the end, it's a DM's call. But I personally would allow players to cast it on a moving ship with no repercussions. The cinematic imagery of a party using a force-field like spell in a last stand against a school of sahuagin is just to appealing. :smallbiggrin:

Keravath
2018-10-04, 12:00 PM
Leomunds tiny hut is not the only spell to use the word immobile ...

Forcecage (level 7) - An immobile, invisible, cube-shaped prison
Globe of Invulnerability (level 6) - An immobile, faintly shimmering barrier

Forcecage and Globe of Invulnerability are then much less useful perhaps on a moving ship.


Also, if you cast a wall spell does it move? Most of the wall spells are cast on a solid surface so if that surface is moving then presumably the spell will move as well. However, wall of force is cast at a point in space BUT it can be free floating or resting on a surface. If it is resting on a surface does a wall of force move with that surface but is otherwise immobile if cast free floating at a point in space?

Joe the Rat
2018-10-04, 12:19 PM
How much of an impact would it be to give the caster the option - if the wall or effect fits (more or less) entirely "on" a surface, you can anchor it to that surface. Wall of Fire (oops?), or something like Hunger of Hadar (big oops) can sit on the deck of the ship, or "on the water" leaving a hazard for pursuers.

Onos
2018-10-04, 12:41 PM
There's a remarkably applicable situation in one of Brandon Sanderson's Cosmere novels, where the state in question (Leomunds Tiny Hut here) is immobile relative to the planets gravity well except when used/cast while in a reference frame with sufficiently high momentum (e.g. a high speed train).
While a hard cutoff point will presumably be explored in later novels, this approach could easily allow your DM to set his/her own boundary conditions, explaining why it can be used on a ship but not a horse without "breaking" any of their own internal logic/immersion.
Also, as a houserule perhaps allow it to be cast at a higher level to allow it to move relative to an object chosen upon casting? With progressively higher spell slots allowing faster movement?
In any case this seems fairly controversial and will most likely be coming down to a direct ruling of some sort from your DM.

Ganymede
2018-10-04, 01:15 PM
this approach could easily allow your DM to set his/her own boundary conditions, explaining why it can be used on a ship but not a horse without "breaking" any of their own internal logic/immersion.

In other words, the frame of reference is wherever it would make sense to place a battle mat.

Willie the Duck
2018-10-04, 01:33 PM
While I appreciate your muse in exploring these kinds of questions, I also think that you are overthinking it.


Leomunds tiny hut is not the only spell to use the word immobile ...
Forcecage (level 7) - An immobile, invisible, cube-shaped prison
Globe of Invulnerability (level 6) - An immobile, faintly shimmering barrier

And, I think more to the point, being rather selective about which of the number of times an absolute is referenced in the rules which would cause redonkulous repercussions if applied like a physical law. 'Immobile', 'indestructible', 'impenetrable', 'no,'... these absolutes show up a lot in the game book, and some of them lend themselves to truly staggering insanity if they were truly absolute.

One from a previous edition: in 3.0 D&D, magic weapons could only be broken by being struck by weapons with higher pluses. I know at least one player in my first 3.0 group suggested using +1 weapons we'd outgrown as structural members with which to support infinitely heavy things (which could never break the weapons, since they weren't +2 items). I think there's even an online term for that for 3e: tippyverse (http://www.giantitp.com/forums/showthread.php?222007-The-Definitive-Guide-to-the-Tippyverse-By-Emperor-Tippy)--take the game rules at face value and extrapolate from there.

Usually resolving these things involves arguments akin to schoolyard debates over what happens if the Juggernaut (an unstoppable force) runs into the Blob (an immovable object) -- there is no one right answer.

My personal preferred solution is to remember that D&D magic is almost always anthropocentric (secondary definition: "interpreting or regarding the world in terms of human values and experiences") -- magic doesn't work on physical levels, but on human-perspective ones. Heat Metal doesn't provide a set amount of joules of thermal energy into a defined mass of elementally-metal material, it heats one metal 'object' to a certain temperature (or at least to a state where it does a certain amount of damage to a person touching it, I supposed depending on the specific heat of the given metal, that too would require different temperatures). Likewise, LTH is immobile-- from the perspective of the pseudo-medieval individual who would be defining it as immobile. Of course, what that is is also up for debate, but at least it is a starting point.

I certainly wouldn't rule that the hut would go shooting off into the void (possibly through the ground) as the planet that the PCs may or may not be on moves past the reference frame. I don't even like deciding if the 'world' the PCs are on is a scientifically accurate 'planet' in 'space' or not until the PCs are doing farflung enough adventures to where it becomes relevant. "Round 'Earth', flat 'Earth,' turtles all the way down? Cold vacuum of space or aether and Phlogiston-filled stars stapled to crystal spheres? You'll have to wait until you're able to go check to know for sure."

xroads
2018-10-04, 01:44 PM
My personal preferred solution is to remember that D&D magic is almost always anthropocentric (secondary definition: "interpreting or regarding the world in terms of human values and experiences") -- magic doesn't work on physical levels, but on human-perspective ones.

I like that. Kind of like of the house I mention above. A house is typically considered immobile from our viewpoints. But in truth, a houses foundation frequently moves. And freak events like mudslides or earthquakes could shift and/or move a house.

Nifft
2018-10-04, 01:47 PM
I like that. Kind of like of the house I mention above. A house is typically considered immobile from our viewpoints. But in truth, a houses foundation frequently moves. And freak events like mudslides or earthquakes could shift and/or move a house.

I like the idea that a mudslide or earthquake of a scale that would move a house would also dispel / break enchantment anything which required immobility inside its area.

Talionis
2018-10-04, 03:18 PM
I would think about any ruling that allows this to anchor a ship. Is that a benefit you would like to convey? I also would be reticent to allow LTH to damage a ship as the Hut stays anchored and ship is tossed to and fro. I would be scared to give so much power to the spell myself.

I would lend myself either to let it attach to very large ships, but not to wagons, etc. Or to just let the spell fall off like it would on the ancient dragon.

I don't think the power level of the spell should be taken into account and not convey vastly more power to my characters than I intended.

stoutstien
2018-10-04, 03:21 PM
So if your on a boat moving let's say 30 feet per turn and the deck is covered in enemy and you cast cloud of daggers at the Kell does the spell move across the ship damaging all in it's path with no save? Spell states you fill the air so no point of reference for itv to be lock to

KorvinStarmast
2018-10-04, 03:30 PM
So if your on a boat moving let's say 30 feet per turn and the deck is covered in enemy and you cast cloud of daggers at the Kell does the spell move across the ship damaging all in it's path with no save? Spell states you fill the air so no point of reference for itv to be lock to
Please ask that separately.
While I don't see why the caster can't perceive a point over the deck of a ship as "fixed" since he also is on the ship, I understand the point you are driving at.

stoutstien
2018-10-04, 05:09 PM
Please ask that separately.
While I don't see why the caster can't perceive a point over the deck of a ship as "fixed" since he also is on the ship, I understand the point you are driving at.
I wasn't trying to be obtuse or derail the thread. I figure this is more about how spells interact with the world.

Lonely Tylenol
2018-10-04, 08:36 PM
So what I’m understanding from reading this thread, as a DM of a high seas campaign, is I should be *very* worried about the possibility of a player using Leomund’s Tiny Hut to total most sailing vessels?

JackPhoenix
2018-10-04, 09:55 PM
So what I’m understanding from reading this thread, as a DM of a high seas campaign, is I should be *very* worried about the possibility of a player using Leomund’s Tiny Hut to total most sailing vessels?

No. As a DM, the spell does whatever you want it to do. If you say that the spell move with the ship, it moves with the ship. If you say that the ship counts as object inside the hut, and thus can pass through, that's what happens.

NaughtyTiger
2018-10-05, 08:42 AM
Abeir-Toril is stationary, the gods move the celestial bodies at their whim. +12 in religion over here.

Willie the Duck
2018-10-05, 09:01 AM
So what I’m understanding from reading this thread, as a DM of a high seas campaign, is I should be *very* worried about the possibility of a player using Leomund’s Tiny Hut to total most sailing vessels?

I think that's where we (by which I mean the DM) decides just how immovable or invulnerable they want the Tiny Hut to be. Even the D&D-historic poster child for immovability, the immovable rod, has limits to its immovability (8000 lbs, or DC 30 Strength check). If you want a random stowaway/saboteur wizard to be able to devastate a moving vessel by casting the spell below decks or right in front of the ship, declare the immovability and invulnerability to be paramount. If you consider that outside the power level or tone of 3rd level wizard spells, declare that there is a limit to one or the other, and that limit is below the force of a fast moving, massive vessel.

Segev
2018-10-05, 01:05 PM
In other words, the frame of reference is wherever it would make sense to place a battle mat.This is a very succinct way of putting what I would have tried to say.

I will, however, still express my reasoning. To me, the spell should be stationary with respect to its immediate environment. If you're trying to use it as a mobile archery platform, it probably will fail unless your idea of "mobile platform" approaches "make that house-sized building get up and move."

Most of the worst exploits, though, are still obviated by the clause requiring the caster to stay inside it. Even if it's a really big wagon-platform, stretching this leeway to its limits, you're not really doing more than using it to travel in comfort and safety. The worst exploit possible is probably as something charging through enemy lines so that people can use it like a tank to shoot out of and lean in and out of. At which point destroying the wagon underneath is going to suffice. You can't have it protect what's supporting it very well, after all.

I'd probably put my limits higher, though, since "Tiny Hut Tanks" aren't a standard battle tactic in war. :P


So what I’m understanding from reading this thread, as a DM of a high seas campaign, is I should be *very* worried about the possibility of a player using Leomund’s Tiny Hut to total most sailing vessels?


No. As a DM, the spell does whatever you want it to do. If you say that the spell move with the ship, it moves with the ship. If you say that the ship counts as object inside the hut, and thus can pass through, that's what happens.
As JackPhoenix says, here, Lonely Tylenol, you only need to be concerned if you rule it that way. If you rule it as being stationary on the boat's deck, then it's fine.

xroads
2018-10-05, 01:28 PM
The worst exploit possible is probably as something charging through enemy lines so that people can use it like a tank to shoot out of and lean in and out of. At which point destroying the wagon underneath is going to suffice. You can't have it protect what's supporting it very well, after all.


Plus, you don't even have to destroy the wagon. Since most games take place inside of dungeons of one type or another, just throw in a few narrow corridors or cliffs. Suddenly, the tactic loses it's appeal.

ciarannihill
2018-10-05, 01:29 PM
Doesn't it just say "immobile" not "immovable"? That is to say it does not and cannot move on it's own, but that doesn't necessarily mean it cannot be moved. The real question is the Immovable Rod (though it has parameters for it's ability to hold things)!

Semantics aside, I had always imagined this spell sort of "anchoring" itself to a location it is manifested at. So when cast on a ship or vehicle, it appears and cannot move from the precise location of that vehicle. On stationary ground, same thing, cannot move from that precise location of ground. If the caster is in a location where it cannot "anchor" to something (like outer space somehow) it is fixed to those precise coordinates in space, but only in those circumstances.

That's how I'd rule it unless the player had an interesting and not gamebreaking (no Tiny Huts as Icebergs) other usage in mind for it, then I might consider allowing it depending on the context.

Beelzebubba
2018-10-05, 01:55 PM
Life would be so much easier if people viewed D&D primarily as a game, and any implied metaphysical system as secondary narrative fluff to make the game better.

So, whenever there's a conflict, ask yourself: "Would this make the game better for all the players?"

- Does it make a certain tactic overpowered to the point it's the only one that makes sense?
- Does it make a class at a certain level incredibly powerful compared to others?
- Does it trivialize an entire portion of the game?
- Is it better than explicit abilities, spells, or powers granted to characters at higher levels?

The answer to those is 'NO, that does not make the game better'.
So, make a ruling in the spirit of 'making it a good game' first.
THEN make up whatever BS 'metaphysics' or explanations that sound good.

D&D does not have to be perfect, or absolutely internally consistent, or completely explained.
It has to be good enough to handle some small contradictions while remaining fun.

Gameplay >>>>> Metaphysical consistency
Fun >>>>>>>>> Winning internet arguments

Lonely Tylenol
2018-10-05, 02:18 PM
No. As a DM, the spell does whatever you want it to do. If you say that the spell move with the ship, it moves with the ship. If you say that the ship counts as object inside the hut, and thus can pass through, that's what happens.


I think that's where we (by which I mean the DM) decides just how immovable or invulnerable they want the Tiny Hut to be. Even the D&D-historic poster child for immovability, the immovable rod, has limits to its immovability (8000 lbs, or DC 30 Strength check). If you want a random stowaway/saboteur wizard to be able to devastate a moving vessel by casting the spell below decks or right in front of the ship, declare the immovability and invulnerability to be paramount. If you consider that outside the power level or tone of 3rd level wizard spells, declare that there is a limit to one or the other, and that limit is below the force of a fast moving, massive vessel.


As JackPhoenix says, here, Lonely Tylenol, you only need to be concerned if you rule it that way. If you rule it as being stationary on the boat's deck, then it's fine.

Sorry for alarming you all, I wasn’t clear. Tongue planted firmly in cheek.

Segev
2018-10-05, 02:21 PM
Sorry for alarming you all, I wasn’t clear. Tongue planted firmly in cheek.

Oh, great, now we have to consider interactions of alarm with relativistic space!?

Willie the Duck
2018-10-05, 02:53 PM
Oh, great, now we have to consider interactions of alarm with relativistic space!?

Nonono, silly. Not alarm, tongues.

Lonely Tylenol
2018-10-05, 07:25 PM
Or worse, absolute space:

“You cast Leomund’s Tiny Hut during sundown?”

“...Yes?”

“Alright. The moment the hut springs into being, it plows into the ground at Mach speeds, crushing everyone inside to death instantly. A magnitude 4 earthquake is felt for miles. In about three hours, someone in Chult is about to have a very bad day.”

KorvinStarmast
2018-10-05, 10:24 PM
Life would be so much easier if people viewed D&D primarily as a game, and any implied metaphysical system as secondary narrative fluff to make the game better.

So, whenever there's a conflict, ask yourself: "Would this make the game better for all the players?"

- Does it make a certain tactic overpowered to the point it's the only one that makes sense?
- Does it make a class at a certain level incredibly powerful compared to others?
- Does it trivialize an entire portion of the game?
- Is it better than explicit abilities, spells, or powers granted to characters at higher levels?

The answer to those is 'NO, that does not make the game better'.
So, make a ruling in the spirit of 'making it a good game' first.
THEN make up whatever BS 'metaphysics' or explanations that sound good.

D&D does not have to be perfect, or absolutely internally consistent, or completely explained.
It has to be good enough to handle some small contradictions while remaining fun.

Gameplay >>>>> Metaphysical consistency
Fun >>>>>>>>> Winning internet arguments I agree. You will admit, however, that taking such a sensible approach removes the fun from two other games:
Overthinking Things on the Internet
Arguing on the Internet
:smallbiggrin:

KorvinStarmast
2018-10-05, 10:25 PM
Or worse, absolute space:

“You cast Leomund’s Tiny Hut during sundown?”

“...Yes?”

“Alright. The moment the hut springs into being, it plows into the ground at Mach speeds, crushing everyone inside to death instantly. A magnitude 4 earthquake is felt for miles. In about three hours, someone in Chult is about to have a very bad day.” So that's how the second sundering happened: someone was careless with LTH.

That explains a lot.

DeadMech
2018-10-06, 05:21 AM
As a player I wouldn't try casting tiny hut on a boat. Leaves too many questions in the air and up to DM fiat. I can imagine some of the dm's I had going in multiple directions with the ruling and I'm generally not interested in breaking a fairly expensive ship in two testing how much of a jerk my DM is feeling. Also I tend to pick tiny hut for camping purposes. If a place has a bed, some walls, and I don't expect to be personally overrun by enemies before I even have time to cast mage armor then I don't generally cast it. I enjoy playing my wizards to a certain level of paranoid. (You would be too if you knew just what dangers infest the universe) But popping down a hut every time we clear a dungeon room or while sleeping in an inn in a place we haven't given everyone a reason to slit our throats in our sleep just cause I can is probably only inviting a magic arms race that I'd rather delay for when I absolutely need an ace in the hole.

As a dm I vote the battlemap method. If a place is big enough to be it's own environment it's probably big enough to avoid most of the worst abuses. Though If I was especially worried the players were trying to make a mobile pillbox for their archers I might be tempted to say that the hut's beneficial effects only work on things also grounded to that anchoring mass. Sailing a boat up to an enemy with a prepared tiny hut on the deck would block unwanted intrusion and projectiles from people that board the boat but not necessarily from other boats. How do I justify this? ... Well I don't really. It's game play concerns. You're gonna force me... uh.. the spell creates a barrier but also radiates out through the medium of the ground... so anything past the constantly flowing water past the hull of the boat... doesn't get affected. And of course flying creatures inherit their properties the energies radiating up from whatever predominant terrain below them... so for the most part the ocean floor and not the boat with the tiny hut.

Still not happy? Fine. Tiny hut doesn't work on a boat or any moving object aside from the planet itself. It lasts far longer than most spells of it's level. The spell itself isn't powering the effect but coercing the local leylines and elemental planar energy waves that matter is composed of into doing it for you. And to do so the hut has to be static to those forces. Stop making me invent make believe physics.

Xetheral
2018-10-06, 10:29 AM
Even if you can't cast it on a ship to cause damage, casting it immediately in front of a ship should have a similar result. (Note, however, that it would be akin to striking a reef: likely damaging the ship, and perhaps causing it to sink, but not destroying it instantly or ripping it in half.)

R.Shackleford
2018-10-06, 10:36 AM
If you are standing still on a moving ship, without moving an inch yourself, are you immobile?

Yes.

It's relative.

I'm on a planet that is moving, am I unable to be immobile?

Tanarii
2018-10-06, 11:52 AM
Even if you can't cast it on a ship to cause damage, casting it immediately in front of a ship should have a similar result. (Note, however, that it would be akin to striking a reef: likely damaging the ship, and perhaps causing it to sink, but not destroying it instantly or ripping it in half.)
A smooth rounded reef. So probably not nearly as much damage.

My first thought was it'd have to be on the seabed too, but I checked the spell it's just a hemisphere over the caster. Totes can be cast while flying, water walking, swimming, etc. Provided you aren't double using concentration (ie Fly and Ritual Casting the Leomund's).

Seems like a good way for a Wizard that's been tossed overboard and about to be keelhauled by a ship to get revenge. Of course, not many Wizards actually prepare the spell. It's usually just in the spellbook so needs to be cast as a ritual.

Xetheral
2018-10-06, 02:24 PM
A smooth rounded reef. So probably not nearly as much damage.

My first thought was it'd have to be on the seabed too, but I checked the spell it's just a hemisphere over the caster. Totes can be cast while flying, water walking, swimming, etc. Provided you aren't double using concentration (ie Fly and Ritual Casting the Leomund's).

Seems like a good way for a Wizard that's been tossed overboard and about to be keelhauled by a ship to get revenge. Of course, not many Wizards actually prepare the spell. It's usually just in the spellbook so needs to be cast as a ritual.

That raises the interesting question of how much of the damage a reef does to a ship is due to the shape/sharpness of the reef, and how much is simply due to the ship's kinetic energy being suddenly concentrated on a small portion of the ship. I would guess the latter would be more important, but I don't know for sure.

And yes, a 5th-level wizard with a swim speed is truly a terror to ships. Sure, they could just light the sails on fire with a Fireball, or they could hull the ship with a well-timed Leomund's Tiny Hut below the waterline.

Remind me to include a group of Wizard-Sirens who demand voluntary sacrifices from passing ships in return for not sinking them. Or to have special forces Sahuagin Wizards block enemy harbors--once the damage is done they can Misty Step deeper to escape.

Edit: I guess in that case it would be Bubbly Step.

lperkins2
2018-10-07, 12:59 AM
A smooth rounded reef. So probably not nearly as much damage.

My first thought was it'd have to be on the seabed too, but I checked the spell it's just a hemisphere over the caster. Totes can be cast while flying, water walking, swimming, etc. Provided you aren't double using concentration (ie Fly and Ritual Casting the Leomund's).

Seems like a good way for a Wizard that's been tossed overboard and about to be keelhauled by a ship to get revenge. Of course, not many Wizards actually prepare the spell. It's usually just in the spellbook so needs to be cast as a ritual.

Gonna need someone else to cast fly, even not casting as a ritual, the casting time is 1 minute, which means concentrating on the spell.


That raises the interesting question of how much of the damage a reef does to a ship is due to the shape/sharpness of the reef, and how much is simply due to the ship's kinetic energy being suddenly concentrated on a small portion of the ship. I would guess the latter would be more important, but I don't know for sure.

And yes, a 5th-level wizard with a swim speed is truly a terror to ships. Sure, they could just light the sails on fire with a Fireball, or they could hull the ship with a well-timed Leomund's Tiny Hut below the waterline.

Remind me to include a group of Wizard-Sirens who demand voluntary sacrifices from passing ships in return for not sinking them. Or to have special forces Sahuagin Wizards block enemy harbors--once the damage is done they can Misty Step deeper to escape.

Edit: I guess in that case it would be Bubbly Step.

So it being round actually means the ship will strike at a tangent to the dome, which means the initial point of impact (before the ship deforms) will be impressively small. The reef, being rough, and having some give, is likely to do comparatively less damage, assuming it doesn't have rocks or previously sunken ships in it at the initial point of contact (and even there, the odds are decent that the hut will be similarly bad).

Tanarii
2018-10-07, 02:08 AM
Gonna need someone else to cast fly, even not casting as a ritual, the casting time is 1 minute, which means concentrating on the spell.

/smh here I was thinking it was an action

Dalebert
2018-10-07, 09:10 PM
Has anyone considered casting it in a space smaller than the spell area? Does it fail? Does it get chopped of at the walls? Spell effects can’t generally pass through solid barriers. This is another issue on a ship. A thin immovable wall that suddenly appeared would unambiguously do serious damage to a ship with momentum. For that matter, any immovable wall would. Have you seen the damage to cars hitting a solid brick wall even at relatively slow speeds, e.g. 30 mph? To those saying they’re not physics gurus, I’ll tell you.

Devastating.

Thus my call is “immobile" is relative to the surface it’s on because that’s less broken.