Can I use Phantasmal Force as a 1-target Mirror Image?

[Cikomyr2]

Imagine you are dueling an enemy, and have access to both Mirror Image and Phantasm Force. Can I use the Phantasm Force to sustain multiple illusions of myselves even after they have been struct by the enemy, and doing an additional 1d6 psychic damage per round because my illusions attack him?

Sort of a defensive/offensive spell? Is that legit?

[MaxWilson]

Imagine you are dueling an enemy, and have access to both Mirror Image and Phantasm Killer. Can I use the Phantasm Killer to sustain multiple illusions of myselves even after they have been struct by the enemy, and doing an additional 1d6 psychic damage per round because my illusions attack him?

Sort of a defensive/offensive spell? Is that legit?

No, you don't control what a victim of Phantasmal Killer sees, much less have the ability to make it mimic your actions.

[prolific_frog]

No, you don't control what a victim of Phantasmal Killer sees, much less have the ability to make it mimic your actions.

I believe he was talking about Phantasmal Force, seeing as he put it in the title and it fits the description.

[Cikomyr2]

I believe he was talking about Phantasmal Force, seeing as he put it in the title and it fits the description.

Sorry, yes. Let me edit that.

[Christew]

I'd say you could certainly have both effects active at the same time (one concentration, one not). You could derive defensive benefit from the Mirror Image illusions and proc 1d6 damage from the Phantasmal Force illusion. However, the wording of Phantasmal Force is singular (a creature) so you could only generate one copy of yourself and you would get no overlap between the two -- i.e. the Mirror Image illusions would not deal damage and the Phantasmal Force illusion would not block attacks.

[MaxWilson]

I believe he was talking about Phantasmal Force, seeing as he put it in the title and it fits the description.

The answer for Phantasmal Force is almost identical: in that case, you can create an image that looks like you, but you don't control it and it won't mirror your actions. Emphasis mine:

You craft an illusion that takes root in the mind of a creature that you can see within range. The target must make an Intelligence saving throw. On a failed save, you create a phantasmal object, creature, or other visible phenomenon of your choice that is no larger than a 10-foot cube and that is perceivable only to the target for the duration. This spell has no effect on undead or constructs.

The phantasm includes sound, temperature, and other stimuli, also evident only to the creature.

The target can use its action to examine the phantasm with an Intelligence (Investigation) check against your spell save DC. If the check succeeds, the target realizes that the phantasm is an illusion, and the spell ends.

While a target is affected by the spell, the target treats the phantasm as if it were real. The target rationalizes any illogical outcomes from interacting with the phantasm. For example, a target attempting to walk across a phantasmal bridge that spans a chasm falls once it steps onto the bridge. If the target survives the fall, it still believes that the bridge exists and comes up with some other explanation for its fall—it was pushed, it slipped, or a strong wind might have knocked it off.

So now it's fighting two versions of you (plus the other PCs). Yes, it could waste actions fighting the illusionary version of you, but at best there's a 50/50% chance of it picking the wrong version of you to concentrate on, and if there are behavioral differences (e.g. the real you is spewing out Fireballs and Eldritch Blasts and other things that aren't intrinsic to your nature and wouldn't be duplicated by an "illusion of a creature [me]") the odds may tilt further in favor of it attacking the real you.

Overall I'd say creating an illusionary duplicate of yourself is probably best reserved for situations where the creature has some kind of special vendetta against you. Otherwise there are probably better fake creatures to mimic than a fake you, e.g. an illusionary Beholder or small dragon. If it's literally a formal duel though I guess creating a duplicate of yourself might work, or it might make him call a timeout for the refs to kick your 'twin' off the field.

[Evaar]

Basically yes, with some caveats.

You can cause the enemy to think it is surrounded by duplicates of you which are attacking it and dealing damage in line with the spell effect. It may try to fight back in response, which as a DM I would rule to be it using its action to make an intelligence check to end the spell.

So yes, there's a way to use illusions of yourself that suits the mechanical description of the spell. What it won't do is provide the effects of the Mirror Image spell. So what I would personally do is randomly decide based on the number of targets available which the enemy will attack. If it's going to attack you, it rolls normally. If it's going to attack the illusion, it makes the Intelligence check.

Phantasmal Force doesn't specifically say it can only create one creature, but I do think that's implied in the description. So I think it's reasonable for a DM to rule that's true, and set a 50/50 chance of the creature attacking you or attacking the illusion.

The damage from Phantasmal Force wouldn't be added to your attacks, but it does happen on your turn. The target would perceive the damage as coming from the illusion, but it doesn't know that it's psychic damage rather than slashing or whatever. So the damage isn't a clue unless the target is so smart that it knows the exact effects of the spell and knows that you're doing more damage than the spell is capable of.

[RSP]

Technically speaking, if you create an illusion of yourself, it may just overlap you, depending how the illusion being rooted in the targets mind reacts with the rationalization of there being two exact duplicates of the same creature.

Something like the illusion is created, and then overlaps the real you in the target’s mind, and they rationalize it as having briefly seen double.

[Chronos]

Rsp29a, that sounds to me a lot like "your spell doesn't work because I, the almighty DM, say so". "Rationalizing away inconsistencies in the illusion" doesn't mean "the illusion does absolutely nothing".

[RSP]

Rsp29a, that sounds to me a lot like "your spell doesn't work because I, the almighty DM, say so". "Rationalizing away inconsistencies in the illusion" doesn't mean "the illusion does absolutely nothing".

RAW, you’d still get the psychic damage; it’s not doing nothing.

As for the spell: the illusion only exists in the target’s mind. It doesn’t actually appear to be anywhere else to anyone else. It isn’t controlled by the caster, but by the target’s mind.

The target will rationalize inconsistencies caused by the spell away. In the in-game world, particularly high magic settings like FR, seeing two of the exact same people, dressed the same way, same equipment, the first way the brain probably rationalizes something is that it is an illusion. The brain goes “am I seeing this right?”

So the rational thought is “it’s an illusion”, but since we’re defending that it’s a magical illusion, the brain rationalizes it as an optical illusion.

This is true even if the creature has no idea of magic as I’m sure we’ve all had moments of double vision at some point. What’s the more likely event in terms of being the more rational event: I’m briefly seeing double in the stress of combat, or a second being popped into existence that is the exact same as the one I’m supposed to duel right now?

The former seems the much more likely way the brain would rationalize the event.

Obviously, rule as what you think is most fun for your table (or however you’d like). (Side note: making an illusion of one’s self isn’t the best use of this spell anyway. Even in this dueling scenario, what’s worse: facing two of the person you’re supposed to duel; or facing, say, the person you’re supposed to duel and, say, the judge who’s working the duel to keep it fair? The latter would be a lot more worrisome than the former, I’d imagine.)

[Cikomyr2]

RAW, you’d still get the psychic damage; it’s not doing nothing.

As for the spell: the illusion only exists in the target’s mind. It doesn’t actually appear to be anywhere else to anyone else. It isn’t controlled by the caster, but by the target’s mind.

The target will rationalize inconsistencies caused by the spell away. In the in-game world, particularly high magic settings like FR, seeing two of the exact same people, dressed the same way, same equipment, the first way the brain probably rationalizes something is that it is an illusion. The brain goes “am I seeing this right?”

So the rational thought is “it’s an illusion”, but since we’re defending that it’s a magical illusion, the brain rationalizes it as an optical illusion.

This is true even if the creature has no idea of magic as I’m sure we’ve all had moments of double vision at some point. What’s the more likely event in terms of being the more rational event: I’m briefly seeing double in the stress of combat, or a second being popped into existence that is the exact same as the one I’m supposed to duel right now?

The former seems the much more likely way the brain would rationalize the event.

Obviously, rule as what you think is most fun for your table (or however you’d like). (Side note: making an illusion of one’s self isn’t the best use of this spell anyway. Even in this dueling scenario, what’s worse: facing two of the person you’re supposed to duel; or facing, say, the person you’re supposed to duel and, say, the judge who’s working the duel to keep it fair? The latter would be a lot more worrisome than the former, I’d imagine.)

Alternatively, when you live in a world where you know magic exist, the idea that the guy in front of you created a duplicate of itself to fight you isn't entirely impossible either. The kind could just accept "****, he's used a spell to duplicate himself, and I can't seem to hit him"

[RSP]

Alternatively, when you live in a world where you know magic exist, the idea that the guy in front of you created a duplicate of itself to fight you isn't entirely impossible either. The kind could just accept "****, he's used a spell to duplicate himself, and I can't seem to hit him"

Sure, though I’d imagine the idea of creating an illusion (accomplished by even the lowest level of casters) is much more readily understood in society than creating actual life (Simulacrum).

I’d imagine two high powered Wizards dueling would be more likely to have their brains accept an actual created being than two commoners, though depending on what they know, that certainly could vary.

[Cikomyr2]

Sure, though I’d imagine the idea of creating an illusion (accomplished by even the lowest level of casters) is much more readily understood in society than creating actual life (Simulacrum).

I’d imagine two high powered Wizards dueling would be more likely to have their brains accept an actual created being than two commoners, though depending on what they know, that certainly could vary.

That's where the Int saves comes.

[Chronos]

The victim sees the actual wizard: That much is clear. And the victim sees the illusion of the wizard, for that is what the spell does. The victim then comes up with some rationalization to explain what he sees. The most logical explanation, of course, is that it's an illusion, but the victim has magic messing with his mind that prevents him from reaching that obvious conclusion. So he's forced to come up with something else. Maybe he thinks that the wizard created a duplicate out of thin air. Maybe he thinks that the wizard's twin sister just showed up to help her. Maybe he thinks that it's someone disguised as the wizard. But no matter what, he still thinks there are two real creatures there who look like the wizard, because that's what the spell does.

[RSP]

That's where the Int saves comes.

Not really. The Int Save is to see if the spell takes effect - it happens before any illusion appears.

The Action to see if it’s an illusion is actually an Int (Investigation) Check.