For the Displacer Beast the text literally says it displaces light to make it appear away from its actual location. I imagine this is less like projecting an image of itself but rather like the displacement we see when viewing something through water, only exaggerated. This isn't projecting an image of itself, but it is projecting an illusion to confuse the visual senses by affecting the light you use to see.
Perhaps it can be thought of like this: take an object, put it on a table across the room. Look at it and close one eye. Now close that and open the other. Repeat, quickly. The object will seem to be in different places, even though it's only in one. The beast's trick is like a magnified version of that. It looks to be in a separate place even though its not. You're still seeing it, rather than an illusory image, and this is why you can still target it normally (it's not invisible or obscured) - but your vision of it is shifted, so attack rolls are at disadvantage.
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For the Displacer Beast the text literally says it displaces light to make it appear away from its actual location. I imagine this is less like projecting an image of itself but rather like the displacement we see when viewing something through water, only exaggerated. This isn't projecting an image of itself, but it is projecting an illusion to confuse the visual senses by affecting the light you use to see.
Perhaps it can be thought of like this: take an object, put it on a table across the room. Look at it and close one eye. Now close that and open the other. Repeat, quickly. The object will seem to be in different places, even though it's only in one. The beast's trick is like a magnified version of that. It looks to be in a separate place even though its not. You're still seeing it, rather than an illusory image, and this is why you can still target it normally (it's not invisible or obscured) - but your vision of it is shifted, so attack rolls are at disadvantage.
I understand that argument. However it also says 'projects an illusion.' It is flavour text vs the description of the actual game mechanic.
Sure but "projecting an illusion" has no defined game mechanic.
The choice in phrasing could just mean projecting illusion magic. It projects something that causes the light to be displaced. I think choosing to interpret it anything more specifically, since there's no definition or ruling within the books to back it up, is just overcomplicating it.
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Yeah, gotta disagree with you there. Magic Missile still requires you to target a creature (it uses the same language of creatures and targeting as any other spell attack), so the roll to retarget still occurs per Mirror Image. Now it would still automatically hit (and remove) the image though if redirected
Targeting with an attack. MM does not involve an attack. I'm not holding up JC as the gospel, 'cause Lord knows I vehemently disagree with a lot of what he says, but I agree with him on this. MM is a very specific spell that does not function like.. well, anything else really in 5e. MM involves no targeting; you automatically hit whatever you intend to hit. The only thing that hard-counters MM is Shield, as intended.
[edit] The point to be made here is that Mirror Image only functions against actions involving an attack roll. MI doesn't function against anything calling for a saving throw either.
See my magic missile questions in the prior post. Note that magic missile does require that you can see the target. Say instead of mirror image, there were four identical appearing actual creatures. Can you specify one by name even though you do not know which of the four that is and have magic missile automatically hit them? Personally I would say no. Magic Missile is good enough as is without being some sort of identity detector or proof against all illusions and disguises.
Edit: And now you have a strange version of Jesus Christ, Superstar stuck in my head.... Hey JC, JC, let's play D&D, sanna hey, sanna ho, superstar!
Magic Missile knows, and I cannot stress enough how that is the bottom line. Unless countered by Shield, Magic Missile is guaranteed damage.
That is the entire purpose of the spell in 5e. It does less than the average damage per spell level, for primary damage spells, in exchange for automatic hits.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Yeah, gotta disagree with you there. Magic Missile still requires you to target a creature (it uses the same language of creatures and targeting as any other spell attack), so the roll to retarget still occurs per Mirror Image. Now it would still automatically hit (and remove) the image though if redirected
Mirror Image triggers when you are targeted with an Attack. Magic Missile requires no Attack.
Spells that force Saving Throws also bypass Mirror Image. Even Cantrips from Acid Splash to Vicious Mockery that force saves bypass Mirror Image. Why shouldn’t an actual leveled spell?
If i cast mirror image with cloak of displacement, does that mean the enemy gets disadvantage on my duplicates?
Yes. How is this not simple to understand?
Cloak of Displacement
While you wear this cloak, it projects an illusion that makes you appear to be standing in a place near your actual location, causing any creature to have disadvantage on attack rolls against you.
Mirror Image
Three illusory duplicates of yourself appear in your space. Until the spell ends, the duplicates move with you and mimic your actions, shifting position so it's impossible to track which image is real. You can use your action to dismiss the illusory duplicates.
Each time a creature targets you with an attack during the spell's duration, roll a d20 to determine whether the attack instead targets one of your duplicates.
The cloak grants disadvantage to attacks made against you. Mirror Image triggers when a creature makes an attack against you.
An attack is being made against you. That attack is made at disadvantage. For all intents and purposes, the enemy is making their attack roll right here and now (at disadvantage). Whether the DM/player physically rolls their d20's now or later is irrelevant, but it logistically happens at precisely this point.
The defender now rolls a d20 to determine whether the attack, which has logistically already been made (at disadvantage), is directed at their self or an MI. Resolve the end result.
This is not hard.
Disclaimer: I am pretty sure I have done the math wrong but I think I am close. If I am terribly off please correct me. Otherwise, let me live in bliss.
So, if a spellcaster with a 14 AC (Mage Armor and +1 from DEX) has a Cloak of Displacement and Mirror Image cast you now only have around a 5% chance to hit him if I did my math right.
Let's just say they are a strange caster and went with a high DEX and get +3. Now you have a 1% chance to hit them. By the way, I rounded up since all the decimals get stupid.
Worse an Eldritch Knight. Now they have plate and a shield plus the above. Chance to hit has now become .somereallylongandreallyreallysmallnumber%.
Yeah, this might be RAW but it is not likely RAI and is certainly not RAF (unless you are an insane munchkin who just likes breaking the spirits of all who game with you).
... And that's why my interpretation (and personal ruling regardess of RAW) is that the disadvantage is only to the caster and not to the mirror image.
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Disclaimer: I am pretty sure I have done the math wrong but I think I am close. If I am terribly off please correct me. Otherwise, let me live in bliss.
So, if a spellcaster with a 14 AC (Mage Armor and +1 from DEX) has a Cloak of Displacement and Blur cast you now only have around a 5% chance to hit him if I did my math right.
Disadvantage does not stack, and you can't calculate the probability of a hit without including what the attacker's to-hit bonus is.
+6 is a fair assumption to start with, and that would leave you with a 42.25% chance to hit that 14 AC with disadvantage. That's not unexpected as 14 AC is very low by standards for a PC.
36% chance to hit against 15 AC, 30.25% to hit against 16 AC, 25% to hit against 17 AC, 20.25% to hit against 18 AC, and so on.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Disclaimer: I am pretty sure I have done the math wrong but I think I am close. If I am terribly off please correct me. Otherwise, let me live in bliss.
So, if a spellcaster with a 14 AC (Mage Armor and +1 from DEX) has a Cloak of Displacement and Blur cast you now only have around a 5% chance to hit him if I did my math right.
Disadvantage does not stack, and you can't calculate the probability of a hit without including what the attacker's to-hit bonus is.
+6 is a fair assumption to start with, and that would leave you with a 42.25% chance to hit that 14 AC with disadvantage. That's not unexpected as 14 AC is very low by standards for a PC.
36% chance to hit against 15 AC, 30.25% to hit against 16 AC, 25% to hit against 17 AC, 20.25% to hit against 18 AC, and so on.
Yes but that's only factoring the disadvantage.
Now factor the Mirror Images and the average battle being about 10 rounds.
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Disadvantage does not stack, and you can't calculate the probability of a hit without including what the attacker's to-hit bonus is.
I didn't stack the Disadvantage. Just poor math and next time I will include attack bonuses and try to show more work to make it easier. Don't know where (or if) I went wrong with my math so I can't say that I understand yours.
Edit: Not sure you are taking into account Mirror Image in your math. It is a completely separate dice roll and has an effect on the outcome so will change the probability. Your math just looks like Disadvantage vs an AC.
So, if a spellcaster with a 14 AC (Mage Armor and +1 from DEX) has a Cloak of Displacement andBlurcast you now only have around a 5% chance to hit him if I did my math right.
Yeah, I thought you were trying to calculate without MI, so that's what I addressed. If you want to know the real probability of outcomes on this combo, you need to integrate a multivariate (discrete AC formulas) probability density function. Ironically, I just got done helping a friend understand that, but I won't bore anyone here. :P
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Yeah, I thought you were trying to calculate without MI, so that's what I addressed. If you want to know the real probability of outcomes on this combo, you need to integrate a multivariate (discrete AC formulas) probability density function. Ironically, I just got done helping a friend understand that, but I won't bore anyone here. :P
I'd be interested to know. How well I can follow the math is ... highly debatable, not sure I'd have the brainpower to follow or do the math.. but I'm interested.
I can't imagine it being high.
The Cloak of Displacement is a mid-to-high level item so it'll be hard to properly say what Dex the caster would have or the attack bonus of enemies. But Blur is nearly identical in effect and casters can get that from 5th Level. Going Point Buy, we can assume they are quite likely to get +3 or +4 to the Dex. So perhaps +3 for the Dex is good for calculating probabilities?
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Click ✨ HERE ✨ For My Youtube Videos featuring Guides, Tips & Tricks for using D&D Beyond. Need help with Homebrew? Check out ✨ thisFAQ/Guide thread ✨ by IamSposta.
Yeah, I thought you were trying to calculate without MI, so that's what I addressed. If you want to know the real probability of outcomes on this combo, you need to integrate a multivariate (discrete AC formulas) probability density function. Ironically, I just got done helping a friend understand that, but I won't bore anyone here. :P
Put it in a video and have what looks like a crazy near 70-year-old jump up and down and get all excited like a 5-year-old with a new toy. Then I would pay attention.
Okay, so the basic idea is that we're trying to calculate a joint probability distribution for multiple variables, and not all of the variables are independent or discrete. We have a simple formula for calculating the chance to hit which is (21+Attack Bonus - Target AC)/20, where Attack Bonus and Target AC are both variables. Attack Bonus is always going to be a discrete integer in actuality, but can also be substituted with the actual attack bonus formula if we're modeling a calculator. Target AC, however, is far more important because that is a dependent variable here; the formula changes based on the outcome of rolling MI, and the probability of successfully shifting to a duplicate is dependent on how many duplicates the caster has. We could even incorporate the probability of a the resulting target having an additional bonus from cover... point being there are way too many conditionals to reasonably calculate in a matrix, so we have to integrate with respect to multiple variable functions.
In particular, we have a function for target AC in which, let's call it f(y)={ Duplicate AC where y= successful MI roll, Caster AC where y=unsuccessful MI roll}. What qualifies as a success for f(y) is dependent on the condition of how many duplicates the caster has. Again, in reality, the # of duplicates component is also discrete, but it's easier to just double-integrate at this point instead of trying to calculate all the permutations of a huge matrix.
Now most of our variables are discrete, so it's not hard to solve a more narrow matrix if you know the actual Attack Bonus, Caster AC, Duplicate AC, # of active Duplicates, and whether there is advantage/disadvantage in effect on the attack roll. I'll demonstrate using the same +6 bonus (at disadvantage), 14 caster AC, 11 Duplicate AC, and all 3 Duplicates active that I used before. The resulting matrix has 4 columns for outcomes which all involve 2 dice rolled ( 2 hits, 2 misses, hit/miss, and miss/hit), and 2 rows for the relevant AC (success on MI, and failure on MI). We also have to keep in mind that any result with one miss means the entire outcome is equivalent to a miss (disadvantage), so the resultant matrix can be summarized.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I finally got off my rear and modeled it in Excel. What I am seeing:
Caster AC: 14 (Mage Armor +1 DEX)
Opposing to Hit bonus: +6
Defense buffs: Cloak of Displacement, Mirror Image (3 Images)
I ran 100 iterations. 11% of the time you hit the caster. ( I think my math is now only slightly different cause I'm not using decimals like Sigreds)
The good thing with my model is I can just change the starting AC and it runs the iterations and pumps out a % at the end. The Eldritch Knight with a 20 AC gets fun :) a steady 2% chance to hit under these conditions.
I could post up the rest but once again just being lazy.
The nice thing about computing as a double/triple/quadruple integral is that you can compute the probability of an entire range of conditions at once. If you don't know attack bonus, you can replace that component of the to-hit calc with an integral evaluated from x <= f(x) <= X. Integrals are awesome. :-)
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
My interpretation of the cloak of displacement is that the illusion sort of moves your perceived location -- not that it makes a copy of you at a new location like mirror image does. Like, you look like you're a few inches away from where you really are so you can still be directly targeted, but just at disadvantage since the attacker is slightly more likely to miss now. Similar to the Blur spell.
As for the original question, the best answer was given back on Post #20 (It's weird how many posts are missing from this thread). Mirror Image is resolved first to determine what is being targeted. Then, if you are being targeted, the attacker gets disadvantage on the attack roll against you because of the cloak.
For the Displacer Beast the text literally says it displaces light to make it appear away from its actual location. I imagine this is less like projecting an image of itself but rather like the displacement we see when viewing something through water, only exaggerated. This isn't projecting an image of itself, but it is projecting an illusion to confuse the visual senses by affecting the light you use to see.
Perhaps it can be thought of like this: take an object, put it on a table across the room. Look at it and close one eye. Now close that and open the other. Repeat, quickly. The object will seem to be in different places, even though it's only in one. The beast's trick is like a magnified version of that. It looks to be in a separate place even though its not. You're still seeing it, rather than an illusory image, and this is why you can still target it normally (it's not invisible or obscured) - but your vision of it is shifted, so attack rolls are at disadvantage.
Click ✨ HERE ✨ For My Youtube Videos featuring Guides, Tips & Tricks for using D&D Beyond.
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Sure but "projecting an illusion" has no defined game mechanic.
The choice in phrasing could just mean projecting illusion magic. It projects something that causes the light to be displaced. I think choosing to interpret it anything more specifically, since there's no definition or ruling within the books to back it up, is just overcomplicating it.
Click ✨ HERE ✨ For My Youtube Videos featuring Guides, Tips & Tricks for using D&D Beyond.
Need help with Homebrew? Check out ✨ this FAQ/Guide thread ✨ by IamSposta.
Magic Missile knows, and I cannot stress enough how that is the bottom line. Unless countered by Shield, Magic Missile is guaranteed damage.
That is the entire purpose of the spell in 5e. It does less than the average damage per spell level, for primary damage spells, in exchange for automatic hits.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Mirror Image triggers when you are targeted with an Attack. Magic Missile requires no Attack.
Spells that force Saving Throws also bypass Mirror Image. Even Cantrips from Acid Splash to Vicious Mockery that force saves bypass Mirror Image. Why shouldn’t an actual leveled spell?
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Disclaimer: I am pretty sure I have done the math wrong but I think I am close. If I am terribly off please correct me. Otherwise, let me live in bliss.
So, if a spellcaster with a 14 AC (Mage Armor and +1 from DEX) has a Cloak of Displacement and Mirror Image cast you now only have around a 5% chance to hit him if I did my math right.
Let's just say they are a strange caster and went with a high DEX and get +3. Now you have a 1% chance to hit them. By the way, I rounded up since all the decimals get stupid.
Worse an Eldritch Knight. Now they have plate and a shield plus the above. Chance to hit has now become .somereallylongandreallyreallysmallnumber%.
Yeah, this might be RAW but it is not likely RAI and is certainly not RAF (unless you are an insane munchkin who just likes breaking the spirits of all who game with you).
Edit: Changed Blur to Mirror Image.
... And that's why my interpretation (and personal ruling regardess of RAW) is that the disadvantage is only to the caster and not to the mirror image.
Click ✨ HERE ✨ For My Youtube Videos featuring Guides, Tips & Tricks for using D&D Beyond.
Need help with Homebrew? Check out ✨ this FAQ/Guide thread ✨ by IamSposta.
Disadvantage does not stack, and you can't calculate the probability of a hit without including what the attacker's to-hit bonus is.
+6 is a fair assumption to start with, and that would leave you with a 42.25% chance to hit that 14 AC with disadvantage. That's not unexpected as 14 AC is very low by standards for a PC.
36% chance to hit against 15 AC, 30.25% to hit against 16 AC, 25% to hit against 17 AC, 20.25% to hit against 18 AC, and so on.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Yes but that's only factoring the disadvantage.
Now factor the Mirror Images and the average battle being about 10 rounds.
Click ✨ HERE ✨ For My Youtube Videos featuring Guides, Tips & Tricks for using D&D Beyond.
Need help with Homebrew? Check out ✨ this FAQ/Guide thread ✨ by IamSposta.
I didn't stack the Disadvantage. Just poor math and next time I will include attack bonuses and try to show more work to make it easier. Don't know where (or if) I went wrong with my math so I can't say that I understand yours.
Edit: Not sure you are taking into account Mirror Image in your math. It is a completely separate dice roll and has an effect on the outcome so will change the probability. Your math just looks like Disadvantage vs an AC.
2nd Edit: Cyb3rM1nd beat me to it just barely. >.>
I meant Mirror Image right there not Blur. Sorry.
Yeah, I thought you were trying to calculate without MI, so that's what I addressed. If you want to know the real probability of outcomes on this combo, you need to integrate a multivariate (discrete AC formulas) probability density function. Ironically, I just got done helping a friend understand that, but I won't bore anyone here. :P
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I'd be interested to know. How well I can follow the math is ... highly debatable, not sure I'd have the brainpower to follow or do the math.. but I'm interested.
I can't imagine it being high.
The Cloak of Displacement is a mid-to-high level item so it'll be hard to properly say what Dex the caster would have or the attack bonus of enemies. But Blur is nearly identical in effect and casters can get that from 5th Level. Going Point Buy, we can assume they are quite likely to get +3 or +4 to the Dex. So perhaps +3 for the Dex is good for calculating probabilities?
Click ✨ HERE ✨ For My Youtube Videos featuring Guides, Tips & Tricks for using D&D Beyond.
Need help with Homebrew? Check out ✨ this FAQ/Guide thread ✨ by IamSposta.
Put it in a video and have what looks like a crazy near 70-year-old jump up and down and get all excited like a 5-year-old with a new toy. Then I would pay attention.
For reference: Numberphile Tentacles Akimbo
Okay, so the basic idea is that we're trying to calculate a joint probability distribution for multiple variables, and not all of the variables are independent or discrete. We have a simple formula for calculating the chance to hit which is (21+Attack Bonus - Target AC)/20, where Attack Bonus and Target AC are both variables. Attack Bonus is always going to be a discrete integer in actuality, but can also be substituted with the actual attack bonus formula if we're modeling a calculator. Target AC, however, is far more important because that is a dependent variable here; the formula changes based on the outcome of rolling MI, and the probability of successfully shifting to a duplicate is dependent on how many duplicates the caster has. We could even incorporate the probability of a the resulting target having an additional bonus from cover... point being there are way too many conditionals to reasonably calculate in a matrix, so we have to integrate with respect to multiple variable functions.
In particular, we have a function for target AC in which, let's call it f(y)={ Duplicate AC where y= successful MI roll, Caster AC where y=unsuccessful MI roll}. What qualifies as a success for f(y) is dependent on the condition of how many duplicates the caster has. Again, in reality, the # of duplicates component is also discrete, but it's easier to just double-integrate at this point instead of trying to calculate all the permutations of a huge matrix.
Now most of our variables are discrete, so it's not hard to solve a more narrow matrix if you know the actual Attack Bonus, Caster AC, Duplicate AC, # of active Duplicates, and whether there is advantage/disadvantage in effect on the attack roll. I'll demonstrate using the same +6 bonus (at disadvantage), 14 caster AC, 11 Duplicate AC, and all 3 Duplicates active that I used before. The resulting matrix has 4 columns for outcomes which all involve 2 dice rolled ( 2 hits, 2 misses, hit/miss, and miss/hit), and 2 rows for the relevant AC (success on MI, and failure on MI). We also have to keep in mind that any result with one miss means the entire outcome is equivalent to a miss (disadvantage), so the resultant matrix can be summarized.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
I finally got off my rear and modeled it in Excel. What I am seeing:
Caster AC: 14 (Mage Armor +1 DEX)
Opposing to Hit bonus: +6
Defense buffs: Cloak of Displacement, Mirror Image (3 Images)
I ran 100 iterations. 11% of the time you hit the caster. ( I think my math is now only slightly different cause I'm not using decimals like Sigreds)
The good thing with my model is I can just change the starting AC and it runs the iterations and pumps out a % at the end. The Eldritch Knight with a 20 AC gets fun :) a steady 2% chance to hit under these conditions.
I could post up the rest but once again just being lazy.
The nice thing about computing as a double/triple/quadruple integral is that you can compute the probability of an entire range of conditions at once. If you don't know attack bonus, you can replace that component of the to-hit calc with an integral evaluated from x <= f(x) <= X. Integrals are awesome. :-)
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
My question is. If the cloak of displacement make a illusion of you. Then casting mirror image. Wouldn't there be 5 of you then??
I guess so. From different sources: spell and magic item.
My interpretation of the cloak of displacement is that the illusion sort of moves your perceived location -- not that it makes a copy of you at a new location like mirror image does. Like, you look like you're a few inches away from where you really are so you can still be directly targeted, but just at disadvantage since the attacker is slightly more likely to miss now. Similar to the Blur spell.
As for the original question, the best answer was given back on Post #20 (It's weird how many posts are missing from this thread). Mirror Image is resolved first to determine what is being targeted. Then, if you are being targeted, the attacker gets disadvantage on the attack roll against you because of the cloak.
I also don't think a Cloak of Displacement creates a seperate illusion of you but modify how you appear instead.