D&D 5E Minor Illusion...can it be cast over other objects?

[Springheel]

The description for Minor Illusion says that "physical interaction with the image reveals it to be an illusion, because things can pass through it."

What if the player wants to cast the illusion over top of another object? I have a gnome who wants to cast a minor illusion on copper coins to make them look like gold.

First of all, is that allowed? If not, why not?

Second, if allowed, does touching the coins reveal them to be an illusion? Your hand wouldn't pass through them, since there are actual coins there, and handling copper coins probably doesn't feel much different from handling gold ones to a non-expert.

I can think of lots of similar examples, like making a wooden door look like a wooden wall. Allowed? Would a simple touch reveal that it's an illusion?

 

[NotActuallyTim]

Keeping an Illusions shape similar to whatever it's been cast on should be a major advantage IMO. Making coins look more valuable than they are would be one such very useful trick.

I mean, fooling people is one of the entire points of Illusion spells. As long as those people aren't the super paranoid types.

 

[The Grassy Gnoll]

I'd say yes but.

Eg coins - from a distance sure, but picking them up and removing one from the pile would reveal the illusion.

Eg door - beat in mind the dimensions allowed - AFB but I believe it's up to a 3' on a side, so it probably won't cover the whole door. You could use it to make the handle/lock look like the wood of the door to confuse people for a moment or "swap" the lock to the other side of the door but that's it.

 

[AaronOfBarbaria]

Coins don't usually just differ in metallic make-up or color.

There are also frequently size differences, weight difference, general shape differences, and the difference in what has been imprinted upon the coin. Because of those differences, a physical handling of the coin could notice which details are illusory.

The Player's Handbook has an image of coins on page 143. While there is no mandate saying that coins must have the same appearance in your campaigns as they do in that image, it still serves as a clear example of details which might be noticed as different with physical handling - specifically, the copper coin is a square shape and the gold coin has two inwardly curving sides, so the illusory effect would be noticed by physical contact with the straight edge of the actual coin far from the apparent edge of the illusory coin. And even if trying to use an illusion to make the copper coin look like the platinum coin which is the same general shape, there is the hole in the center of the copper which would be physically felt where an illusion of a triangular shape (I think it is supposed to be a cut diamond).

That's not to say that the detection should be automatic when the illusion has been placed in such a way as to use what is physically present to prevent passing straight through the illusion, just that it should be possible and shouldn't necessarily be non-automatic because the physical handling can be directed at the details that would notice the illusion.

For making a door look like a wall, if it is within the size limit that should be fine as well - but anyone touching it should be able to tell that instead of a wooden wall they are running their hand over a hinge, gap, latch or handle that a wall wouldn't have.

 

[Psikerlord#]

I would probably rule touching the false coins would allow an Int check to see through the illusions (the weight is wrong, or the imprint on it feels wrong, or perhaps the illusion wavers for a moment while touched, revealing the copper beneath, something like that).

 

[Rhenny]

One of the big stipulations for minor image (as opposed to major image) is that the illusion is not movable. Well, at least that's what's implied because there is no mention of being able to move a minor illusion; whereas major illusion has information about making the illusion move.

So...making the coin look gold can be done, but if the coin moves, then what? Also, as soon as anyone else touches the coin, they have interacted with it so their fingers pass through the illusion to the object itself..so does that mean they figure out that it isn't gold?

DM has lots of wiggle room with illusions (always has been that way). I'd probably let others have a free perception check to see if there is something strange about the object in these cases, and if they do an active intelligence investigation check I might grant them advantage.

Personally, I like awarding creative play and giving players a chance to stretch the rules if possible. Not many players choose an illusionist type player so they should get some perks.

 

[Sunseeker]

The way I run minor illusions they are created in a fixed position relative to the ground, that's why it takes an action to move them, they don't move when an object they're cast on/around moves. Prestidigitation would probably be a better choice to "recolor" the coins to silver or gold.

In either case, I would still rule "physical interaction reveals the illusion" to mean that once they picked up the coin, even if the illusion moved with it, they would realize its a fake as say, a copper coin would have different symbols on it than a silver coin, and you'd feel the actual symbols. Per the spell, once they realize, the illusion remains but becomes semi-transparent' to the viewer and thus they'd notice the real coin underneath.

 

[GX.Sigma]

It says "create an image of an object," not "change the appearance of an object" (cf. seeming).

Can you cast it over another object? Sure, since "things pass through it." Of course, "physical interaction with the image reveals it to be an illusion." Nobody would be able to pick up the illusory coin and give it to a merchant in the first place.

 

[Lehrbuch]

What if the player wants to cast the illusion over top of another object? I have a gnome who wants to cast a minor illusion on copper coins to make them look like gold.

First of all, is that allowed?

Absolutely fine.

Second, if allowed, does touching the coins reveal them to be an illusion? Your hand wouldn't pass through them, since there are actual coins there, and handling copper coins probably doesn't feel much different from handling gold ones to a non-expert.

There are two problems here:

One, as others have said, the illusion can't move so that might cause problems if the coins are removed from the pile/chest for inspection. Of course, you could have a few real gold coins on the top of the pile to get around this.

Second, everyone pretty much should be an "expert" in identifying the coins of their local currency. Think about the coins of your own local currency in real life. Different dominations probably have different weights, thicknesses, and sizes. It's not just a matter of the colour and the image imprinted on the surface. And this has been the case for centuries, it is not just about modern sensibilities around provision for the blind and/or fraud detection. For example, look at museum images of the sizes of different Roman coin denominations. A Dupondius is quite different to an Aureus.

You might be able to get away with illusions covering coins when the currency is not local (either foreign coins, or ancient coins retrieved from a dungeon) as the locals might not be very familiar with what the coins should be like. Then again, unusual coins will probably attract greater scrutiny from whomever you are attempting to fool.

 

[NotActuallyTim]

Being able to to notice differences in coins requires familiarity with the coins. I'd argue that most creatures have little to no experience inspecting coinage for forgery, with the exception of officials, merchants and others who engage in tax collection or trade on a routine basis.