Is it possible to create an illusion of nothing?

[Greywander]

Say, for example, you're running down a hallway and a turn into a side passage. Normally in a situation like this, you might try to flatten yourself against the wall, then create an illusion of the wall in front of you. But I'm wondering if, using either Minor Illusion or Silent Image, you could create an illusion of an "empty" passage.

My gut says, "no," because this could be easily exploited to essentially turn anything invisible as long as it stays inside the illusion.

You could create a flat image of an empty passageway, but any kind of inspection would reveal a lack of depth (a higher level illusion spell might be able to do parallax scrolling of things in the flat image to create the appearance of depth, but I doubt Silent Image can). The other option is to create an illusion of a solid object that completely surrounds you (like a crate or piece of furniture), but if there's an empty gap in the illusion, people would be able to see you through the gap. It's probably best to simply create an illusion of a continuous wall that covers the passageway, but guards and such who are familiar with the location are probably going to be asking themselves, "Wasn't there a passageway here?"

[Quoxis]

Normally in a situation like this, you might try to flatten yourself against the wall, then create an illusion of the wall in front of you.

Depending on the bodily measurements of your character this should be the easiest way - guards or whatever is following you are unlikely to notice that a wall is a few inches thicker than normally in the heat of the moment.
If roles were reversed and you tried to b&e a guarded mansion there‘d probably be a bigger chance of failure, but that’s off topic.


You could create a flat image of an empty passageway, but any kind of inspection would reveal a lack of depth (a higher level illusion spell might be able to do parallax scrolling of things in the flat image to create the appearance of depth, but I doubt Silent Image can).

Pretty much what i‘d rule, yeah. Illusion wizards can from level 6 onwards „use [their] action to change the nature of that illusion“, so that might help with parallax scrolling a silent image, if your GM is exceptionally allowing, but eh, i wouldn’t count on it.

[hymer]

Some of it depends on the spell. Minor Illusion specifies sound or object IIRC, and nothing ain't no object - nor a sound. But Invisibility is specifically the illusion of nothing where there's something.

[NinaWu]

You wouldn't be creating an illusion of nothing, you would in fact just be creating an illusion of the passageway behind which the truth would hide. Just like creating a small stone wall and hiding behind it. Creates the same effect as you stated, but creating an illusion of 'nothing' needs an image of something.

[Hand_of_Vecna]

Movies use painted backdrops to add the illusion of depth. I could see an illusionist replicating on of those to create a fake hallway that could make someone walk into a wall or put one ten feet down a hallway they're hiding in forcing a guard to choose randomly which way to go at a fork.

While creating this would be within the boundaries of an image spell, the DM could rule it to be outside the illusionists as it requires developments in art that aren't contemporary to a pseudo medieval world.

[Aimeryan]

Remember that illusions can be 3D as well; should be capable of simulating parallax, limited by the size of the illusion compared to the expected viewing angles it is to be seen from. A narrow bare 5ft hallway should easily be doable with just Minor Illusion.

[hymer]

Remember that illusions can be 3D as well; should be capable of simulating parallax, limited by the size of the illusion compared to the expected viewing angles it is to be seen from. A narrow bare 5ft hallway should easily be doable with just Minor Illusion.
You would have to define a hallway as an object. I don't think most DMs would allow that. And even if the DM is fine with that, there's still the question of whether someone standing in the illusion would be covered by it, when the illusion isn't of anything. If you make an illusion of a grate, can you see people behind it? The same logic should apply to a hallway.
As for the 3D element, if the hallway is only five foot deep, then parallax is no issue. But if it is 100', and the illusory object is only 5' deep, something could well come to seem out of whack when you pass by it, unless the illusion shifts as people moves by it. In which case two people moving by, one behind the other, they could get different results.

[Aimeryan]

You would have to define a hallway as an object. I don't think most DMs would allow that. And even if the DM is fine with that, there's still the question of whether someone standing in the illusion would be covered by it, when the illusion isn't of anything. If you make an illusion of a grate, can you see people behind it? The same logic should apply to a hallway.
As for the 3D element, if the hallway is only five foot deep, then parallax is no issue. But if it is 100', and the illusory object is only 5' deep, something could well come to seem out of whack when you pass by it, unless the illusion shifts as people moves by it. In which case two people moving by, one behind the other, they could get different results.

A model is an object. Similarly, a curved/shaped painting is an object, which works if the hallway has no objects that would require simulating some parallax scrolling (i.e., it is just a hallway).

Yeah, the size and viewing angle differences (as the viewer moves past the illusion) are important to what you can expect to fool people with. Texture, lighting, etc., also comes into play. It is worth mentioning that although the hallway might be 100ft long, where you create the illusion could matter significantly - a guard moving past the hallway giving it a glance down would be a lot easier to fool with an illusion 90ft down the hall (only having to simulate the last 10ft of the hall) than an illusion right adjacent to his path (having to simulate the whole 100ft).