D&D 5E Minor Illusion question

You are trying to apply real world physics to magic. Magic, by definition, takes real world physics and ties them into little tangled knots of mess [or this case iron box].

No, I'm applying physics to the result of the spell. Much the same way a wall of stone spell doesn't create a wall that light passes through, nothing about the image created says light passes through it either unless the person knows it's an illusion.

Our games don't have to be the same, obviously. How you choose to define things in your game is...well, fine for you.

I'm not defining things, I'm following the definition in the book. You of course are welcome to houserule changes to rules as you see fit.

I would also add that it being a cantrip, absolutely, has [or should have] something to do with a given spell's interpretation. Given, also, that the description states it can not "create light" and, so, by extension, can not elicit a change in existing light. So, yes, it being a cantrip does mean light can pass through it...that does not demand you can see inside of or through it...just that this weird ambient light that's in the room seems to "begin" at the edges of the box.

Again... if it isn't creating light... and light just passes through it... THEN YOU CAN'T SEE IT. This is how light works.

D&D spells are, explicitly, tiered into levels of varying power. 3rd level spells are more powerful/reality bending than cantrips. 5th level spells are more powerful/reality bending than 3rd. It is, and has always been, built into the system that a cantrip would/should be less powerful/reality bending than a more powerful/higher "tiered" spell. All Magic, in D&D, is not created equal. [and specifically, in D&D, illusion magic has always been wonky/required some case-by-case adjudication].

This is irrelevant, follow the spell's description.

Again, determining there is an illusion here should not be particularly difficult. But it will/should cause a moment or two to be spent questioning/confused/investigating...by the characters/NPCs, mind. What the players know/can deduce is happening is not [always] what the PCs know/can deduce.

The difficulty of determining the illusion is given by the spell and no, it isn't easy. The DM may decide to make this easier if you do something that makes it really obvious however. Putting it in a room with light isn't something that makes it obvious.

Think of it, maybe, like a one way mirror...kind of...light gets out but doesn't pierce in. You see the outside of the box because of the light in the room/that is being shed from within it...but you do not actually see the source/light inside the box.

If the caster makes a one-way mirror with the spell then it will work like a one-way mirror. The OP did not describe a one-way mirror.

Yes. It's wonky. It's supposed to be. It doesn't make sense when applied to real world physics. It's not supposed to. It's magic.

It isn't the least bit wonky unless you try to add all this one-way-mirror stuff that isn't needed.
 

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This is a fine explanation until one considers that once a creature sees it as an illusion, then weird stuff happens.

For example, illusion of a box on top of a lit torch. Nobody sees the torch because of the illusionary box. The room is pitch dark because the illusion blocks the light. Then one PC interacts with the box and he sees a totally lit room whereas the other PCs still see a pitch dark room. Or even alternatively, he sees the lit torch, but the room is still pitch dark.

However one cuts it, it's wonky.

It's not wonky, it's magic. Magic already does lots of things like target only enemies in an area, always hit a target etc.

Your example isn't an example. It's irrelevant if the light comes directly from a torch or if it hits a wall and bounces off first. It's the same light. In either case if it passes through the image then you can't see the image.

The fact that light passes through for some people and not others due to it being transparent when discovered is again EXACTLY THE SAME regardless of if that light is direct from a torch or if the light is from a torch but bounced off another object first. Same light.

If you can see the light from the torch through the image, than you can see the light from the wall through the image. In other words, you can't see the image.

So yes, with this spell and a bit of setup you can make a light source enemies can't see. Which is no different than the many area spells that only work on friends.
 
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It's not wonky, it's magic. Magic already does lots of things like target only enemies in an area, always hit a target etc.

Your example isn't an example. It's irrelevant if the light comes directly from a torch or if it hits a wall and bounces off first. It's the same light. In either case if it passes through the image then you can't see the image.

The fact that light passes through for some people and not others due to it being transparent when discovered is again EXACTLY THE SAME regardless of if that light is direct from a torch or if the light is from a torch but bounced off another object first. Same light.

If you can see the light from the torch through the image, than you can see the light from the wall through the image. In other words, you can't see the image.

Unless one takes the view that the hue, color, and pattern of any light changes when it interacts with the image to correspond to the image (it does not matter if that light is in front of the image or behind it). Then your "it's magic and the problems with my explanation works because of that" is not necessary. Any light behind the image is altered to conform to the image. The ability to see through the image then becomes the ability to spot the errors in the image and squint past that to see the real light behind.

In any case, this is all just speculation.

Each DM will need to figure out for himself what happens when the illusionary box is placed over the lit torch (or the light spell). Does it now have the power of the darkness spell to obliterate that light, or is it only a cantrip that does not have all of these cool powers?
 

Any light behind the image is altered to conform to the image. The ability to see through the image then becomes the ability to spot the errors in the image and squint past that to see the real light behind.

If this were the case then if there was no light behind the image but only in front of it, then you couldn't see the image, only a weird colored pattern on the wall.

In other words, the image has to reflect light or it doesn't work as the spell describes and as things like Guards and Wards expects.

People are trying to make this far far more complicated than it is because they don't appreciate that light directly from a torch and light from a torch that has bounced off a wall first are effectively the same thing.
 

No, I'm applying physics to the result of the spell.

You say this and then, a few lines from now, defend your interpretation by "This is how light works." You see the contradiction here, right?

Much the same way a wall of stone spell doesn't create a wall that light passes through, nothing about the image created says light passes through it either unless the person knows it's an illusion.

Nooo. Not "Much the same way..." Not at all "the same way." Apples to oranges. Wall of stone conjures up an actual wall of real stone. Obviously light doesn't pass through it. It is nothing at all like conjuring up a Minor Illusion cantrip. It might be comparable to a Major Illusion or a Hallucinatory Terrain...but they are still, ultimately illusions. So, no, not the same thing. To suggest that the way one spell works means it is the way ALL spells work is...well, I don't actually know what it is. Misguided? Impossible? A fool's errand?

Again... if it isn't creating light... and light just passes through it... THEN YOU CAN'T SEE IT. This is how light works.

Saying the same thing over again in capital letters is not going to make your case any stronger or more accurate. I get what you're saying. You are saying: For the creatures in the game world to see the box light can't pass through it. If light isn't reflecting off the illusory surface, their eyes will not perceive the illusion. You are arguing that by creating this illusory box around the torch, you now have a dark room...in which, without darkvision or something, you won't see the box either since now the room is dark...because it seems to be inconceivable, for you, that light might pass through one side of the illusion but not the other.

I am saying, there IS light reflecting off the outside of the box...from the light that is in the room...which is emanating -through the very much not-transparent or translucent box- from the torch within. Yes, it is paradoxical. But there's magic for ya.

I'm getting the feeling this is just something you are not going to/capable of seeing...no pun intended...because you seem stuck in a loop of "but then you can't see the box!"

You don't have to agree with my ruling. I don't have to agree with yours. S'all good in duh 'hood.

The difficulty of determining the illusion is given by the spell and no, it isn't easy. The DM may decide to make this easier if you do something that makes it really obvious however. Putting it in a room with light isn't something that makes it obvious.

Don't believe I ever said it would be easy or "obvious". It should, at least momentarily, cause whoever is seeing it to say "Hey. What's going on here? There's light in the room...but no light source." <investigate, investigate, roll, roll, roll> "How's this box making light?" <touch the box, it disappears> *Poof* Light level in the room doesn't change. "Hmph. Why would someone want to put an illusion over a torch?" At no point was anyone in the room having difficulty seeing, nor automatically seeing through, anything.

If the caster makes a one-way mirror with the spell then it will work like a one-way mirror. The OP did not describe a one-way mirror.

My bad. I thought I was clearly presenting the one-way mirror scenario as an example of what it was working like/how it might be comprehended. Apparently not. Nevermind.

It isn't the least bit wonky unless you try to add all this one-way-mirror stuff that isn't needed.

Ironically, I don't see it as adding anything. Simple interpretation of a simple spell. You get an image, as defined by the spell. The spell's not changing/altering anything else. Seems the obvious, easiest, most flavorful and fairest ruling of the spell in the presented situation.

But...that's for me/my game.

Hope your DM agrees with your assertions so you can enjoy your illusion-use. Happy gaming.B-)
 

So, it seems to me that the interpretation is simpler if the illusion just tricks the viewers mind, similar to an optical illusion. Several of the optical illusions in this gallery at CNN give a little bit of an example of what I mean, specifically the bent lines, and moving spirals.

http://www.cnn.com/2015/02/27/living/gallery/optical-illusions/index.html

I am not saying the minor illusion makes straight lines look bent, but in a similar way it, and other illusion spells present something in their image which tricks the mind into seeing what is not there. So like a real optical illusion, it takes some investigation to determine that the image is not there. In this way, the minor illusion and other illusion spells don't alter anything about the environment, just how the viewers perceive it.

So back to our box for a possible explanation into "what really happens". The caster puts a minor illusion of a box around the torch. The actual illusion itself is a transparent image, but as viewers see it, something about the magic in it causes the object to appear solid to the viewer in a similar way to how our brains fill in data when looking at an optical illusion. While the box appears solid to the viewer of the illusion, the lines of an optical illusion appear bent to the viewer. The "real" image of the illusion is always translucent, just as the optical illusion's lines were always straight.

This allows the illusion to not alter the environment, actually exist in one state while viewers can perceive it as solid or translucent, and be viewed from any distance away. It also goes back to what I would consider to be the original intent of the spell: it is "just an illusion."
 

You say this and then, a few lines from now, defend your interpretation by "This is how light works." You see the contradiction here, right?

There isn't a contradiction. You see applying physics to a magical fireball makes no sense but expecting a fire set by a spell to generate heat is not applying physics to magic, right?

Nooo. Not "Much the same way..." Not at all "the same way." Apples to oranges. Wall of stone conjures up an actual wall of real stone. Obviously light doesn't pass through it. It is nothing at all like conjuring up a Minor Illusion cantrip. It might be comparable to a Major Illusion or a Hallucinatory Terrain...but they are still, ultimately illusions. So, no, not the same thing. To suggest that the way one spell works means it is the way ALL spells work is...well, I don't actually know what it is. Misguided? Impossible? A fool's errand?

In no way have I said all spells work the same. I have said that YOU are applying things to spell that the spell doesn't specify.

Saying the same thing over again in capital letters is not going to make your case any stronger or more accurate.

No, but one would hope you'd bother reading it to understand it rather than keep going on with your preconceived notions of adding lots of things to a spell that aren't there.

I get what you're saying. You are saying: For the creatures in the game world to see the box light can't pass through it. If light isn't reflecting off the illusory surface, their eyes will not perceive the illusion. You are arguing that by creating this illusory box around the torch, you now have a dark room...in which, without darkvision or something, you won't see the box either since now the room is dark...because it seems to be inconceivable, for you, that light might pass through one side of the illusion but not the other.

It's not inconceivable light would pass through. I've given several examples of exactly the opposite, a gem and a one-way mirror.

What you seem to find inconceivable is that a caster can make an object that ISN'T a gem or a one-way mirror. For some reason you've read the spell such that every image is a glittering translucent gem. But making the image translucent, when the spell does not say such, has consequences that make the spell useless.

The only light you are receiving from the spell is coming from other sources in the room. If it does not reflect light like a normal object but instead transmits it, it will NOT look at all like a normal object for many reasons, one of which being lack of shadow.

I am saying, there IS light reflecting off the outside of the box...from the light that is in the room...which is emanating -through the very much not-transparent or translucent box- from the torch within. Yes, it is paradoxical. But there's magic for ya.

That isn't paradoxical, it is contrary to the spell which states explicitly that it does not create light. If it both reflects and transmits light to the proper intensity to appear to be an object it will have to create light or it will only be at half intensity.

I'm getting the feeling this is just something you are not going to/capable of seeing...no pun intended...because you seem stuck in a loop of "but then you can't see the box!"

I see perfectly well how you are misunderstanding how the spell is stated to work and how you don't appreciate the consequences of making the spell far far more complex than it needs to be.

Ironically, I don't see it as adding anything. Simple interpretation of a simple spell. You get an image, as defined by the spell. The spell's not changing/altering anything else. Seems the obvious, easiest, most flavorful and fairest ruling of the spell in the presented situation.

Again, if you have the inside of the box both reflecting light in order to be seen and transmitting light through it, the only way for this not to be at half intensity would be if the box is creating light, and the spell doesn't do that.

You are saying that if you look at this box, because there is a light inside it, you can see the light. Go and look at a lit light bulb for a second. That is what you are saying you are seeing. Anyone looking directly at the box will see a bright retina burning light. In other words they aren't see a box, they're seeing light from behind the box.

You're going to turn around and say no, they don't see a bright spot of light, they just see the light from the torch that isn't directly from the torch. So what you'll really be saying is that you can't see light directly from the torch but you can see light from the torch that goes and bounces off a wall first. So WALLS can see light directly from the torch but your eyes can't. And... why? Nothing about that is in the spell. Further, light that then bounces off the walls then has what effect on the image? None of this makes sense. What does make sense is treating the image like an image and not some super complex sometimes translucent sometimes not light emitting but not light creating sometimes reflecting but not always ball of craziness.
 
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So, it seems to me that the interpretation is simpler if the illusion just tricks the viewers mind, similar to an optical illusion. Several of the optical illusions in this gallery at CNN give a little bit of an example of what I mean, specifically the bent lines, and moving spirals.

Some spells trick the mind and won't work on "mindless" creatures. This isn't one of them, it says it creates an image.

So back to our box for a possible explanation into "what really happens". The caster puts a minor illusion of a box around the torch. The actual illusion itself is a transparent image, but as viewers see it, something about the magic in it causes the object to appear solid to the viewer in a similar way to how our brains fill in data when looking at an optical illusion. While the box appears solid to the viewer of the illusion, the lines of an optical illusion appear bent to the viewer. The "real" image of the illusion is always translucent, just as the optical illusion's lines were always straight.

Regardless of if it's tricking the mind about what light is hitting the retina or if it's altering what light is hitting the retina, it will have the same effect. Something between a light source and an observer will prevent that light source from being seen if that something is opaque.
 

So, it seems to me that the interpretation is simpler if the illusion just tricks the viewers mind, similar to an optical illusion. Several of the optical illusions in this gallery at CNN give a little bit of an example of what I mean, specifically the bent lines, and moving spirals.

http://www.cnn.com/2015/02/27/living/gallery/optical-illusions/index.html

I am not saying the minor illusion makes straight lines look bent, but in a similar way it, and other illusion spells present something in their image which tricks the mind into seeing what is not there. So like a real optical illusion, it takes some investigation to determine that the image is not there. In this way, the minor illusion and other illusion spells don't alter anything about the environment, just how the viewers perceive it.

So back to our box for a possible explanation into "what really happens". The caster puts a minor illusion of a box around the torch. The actual illusion itself is a transparent image, but as viewers see it, something about the magic in it causes the object to appear solid to the viewer in a similar way to how our brains fill in data when looking at an optical illusion. While the box appears solid to the viewer of the illusion, the lines of an optical illusion appear bent to the viewer. The "real" image of the illusion is always translucent, just as the optical illusion's lines were always straight.

This allows the illusion to not alter the environment, actually exist in one state while viewers can perceive it as solid or translucent, and be viewed from any distance away. It also goes back to what I would consider to be the original intent of the spell: it is "just an illusion."

So what does this mean for the torch in the illusionary box in the dark room?

Is the room pitch dark, or does light come through? I suspect that light comes through with this interpretation since the illusion is transparent (or is it translucent, you used both terms).


This, btw, is similar to my earlier explanation. I was viewing it more as errors in the image that allow someone to squint past it. Yours is a real world illusion where a person perceives something in a default way.

One issue with both interpretations is that people auto-fail. In the real world, some people see past some illusions immediately.
 

Some spells trick the mind and won't work on "mindless" creatures. This isn't one of them, it says it creates an image.



Regardless of if it's tricking the mind about what light is hitting the retina or if it's altering what light is hitting the retina, it will have the same effect. Something between a light source and an observer will prevent that light source from being seen if that something is opaque.

Yes, it creates an image, but which mindless creatures are you thinking of?

My thought is that it does not do anything about the light. It doesn't trick the mind into not receiving light or actually block the light. If a viewer looks at our box, their pupils would shrink a bit because they are looking directly at a light source, but they would see the illusion of a box. The translucent image of the box is there, but it is translucent. However the magic of the illusion tricks the viewers mind into filling in the solidness of the box and ignoring what is inside/behind the illusion.

The light from the light source is still seen, but the illusion tricks the mind into filling in the solidness of the illusion so the viewer does not perceive the source of the light as being there.
 

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