Silent Image question

[SangoProduction]

Can you create an illusory wall, upon which you project a scene? Ostensibly, one that looks like the scene you are blocking off, but with the details changed as you desire (such as you not being behind that wall, or projecting a "movie").

[Chronos]

Yes, but it'll look like a wall with a movie playing on it. Unless you can very carefully control the vantage point from which it's seen, it won't fool anybody into thinking the wall's not there.

[Daisy]

Yeah, I've had players try to use this kind of shenanigans to make the party invisible, etc.. Not at my table, you scallywags!

You need to clamp down on this thing quick, or before you know it they'll be using it to blind enemies (image of a black wall over the eyes), gain cover (if they think I'm behind a low wall they'll only aim at the bit they can see, so +4 AC please), all that kind of thing. Clever? Maybe. Spirit of the game? Nope.

[Duke of Urrel]

Can you create an illusory wall, upon which you project a scene? Ostensibly, one that looks like the scene you are blocking off, but with the details changed as you desire (such as you not being behind that wall, or projecting a "movie").

I agree with everything that everyone has said so far, and I have one thing to add.

Spells of the Figment subschool (https://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#figment) can add illusions to a space, but they cannot subtract anything from it, because they cannot make anything that is real seem to be anything other than it is. The only change that a Figment spell can make to a real wall is to cover it up with an illusory wall. As Chronos mentioned, a Figment spell can make a wall look like a movie screen, but it won't look like an open window to observers who approach it too closely.

If you want to make a real wall seem not to be there, you need to use a spell of the Glamer subschool (https://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#glamer). Moreover, you need the Mirage Arcana spell (https://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#figment), or perhaps a more powerful Glamer spell, such as the Screen spell (https://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#figment), to make an artificial structure such as a wall seem not to be there.

[MaxiDuRaritry]

You could always crouch down and project the illusion of a pile of rock or something covering up where you are. There's no functional difference between that and standing in a room while using the illusion to block off the doorway by making it look like a section of wall.

[Fero]

Illusions require DMs to walk a fine line. On one hand, you don't want players to abuse things to the point the game is no longer fun. On the other hand, you also don't want to suck creativity and soul from the game. If you do, your players will turn to video games that can service mechanical gameplay better than any DM ever could. As such, I would encourage you to avoid asking what the rules allow (illusions seldom offer a straight answer) or what is balanced. Instead, ask what is fun. Does this use advance the story and add fun or is the player abusing it to the point of being stale and everyone rolling their eyes? Answering that will answer how you should come down. Rule of Cool works well for illusions.

[Crake]

Yeah, I've had players try to use this kind of shenanigans to make the party invisible, etc.. Not at my table, you scallywags!

You need to clamp down on this thing quick, or before you know it they'll be using it to blind enemies (image of a black wall over the eyes), gain cover (if they think I'm behind a low wall they'll only aim at the bit they can see, so +4 AC please), all that kind of thing. Clever? Maybe. Spirit of the game? Nope.

They wont get cover, but they would definitely get concealment.

[Phhase]

I would personally say yes, but that it would obviously be unmoving, and would only be visually convincing from certain narrow angles or perspectives. You can't create a 2D illusion that violates euclidean space, as least not with a base level unmodified Silent Image. Further, in order to made such a finely detailed and convincing image, I would ask for some sort of tool check or other visual-arts related ability check to see how detailed or convincing they can make it.

That said, with some specialization, combination with other effects, and training, I would eventually allow a player who invested enough to do cool things like that with Silent Image.

Another idea is to use Phantasmal Force. Since the illusion can be moving and is entirely mental, and indeed changes so that the viewer rationalizes the interaction, I feel you could totally use it to make an illusion of a false door to a false room or somesuch. Just one person, but still.

[rel]

Silent image says it let's you create an object, creature, or force then move it around within the size of the effect.
My reading of that is that you can move the created object, but not change it. So a wall painted with a static image to make the room look deeper than it is works, but a wall with a movie playing on it isn't possible.

You can still absolutely place an illusion of a wall, painted or otherwise, to section off part of a room and hide whatever's behind it, but creatures coming across the illusion will get checks to notice that something is off.
And if they do notice something odd and investigate, they get saves to disbelieve the illusion.

[Jay R]

An illusion of a movie screen -- why not?

It will fool somebody neither more nor less than a movie screen fools them, which is to say, almost not at all.