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koeldflare
2009-10-19, 07:50 PM
Like the title implies, I'm wondering how certain spells that grant miss chances work with one another. Specifically I'm looking into the stacking effects of Displacement, Ghostform and Greater Mirror Image.

As a side note: is there any other spells that would stack with this combination? My character won't have a high AC so I'm looking into getting as many miss chances as possible.

Curmudgeon
2009-10-19, 08:04 PM
(Greater) Mirror Image provides illusory doubles, but they go poof when struck. No other magical miss chances affect these doubles. Roll randomly to see whether a double or your person is targeted. Ghostform and Displacement stack on your person, though. Apply each miss chance sequentially.

Ravens_cry
2009-10-19, 08:27 PM
I think Blur does, at least with Mirror Image, as it's purely a visual effect. By stack, I mean your doubles also have a 20% miss chance, even if targeted.

koeldflare
2009-10-19, 08:38 PM
What I mean by stacking miss chances is having many effects that give miss chances, that someone who (if they were to attack me), they would have to roll miss chance after miss chance, hopefully ensuring me an eventual miss.

PairO'Dice Lost
2009-10-19, 10:09 PM
What I mean by stacking miss chances is having many effects that give miss chances, that someone who (if they were to attack me), they would have to roll miss chance after miss chance, hopefully ensuring me an eventual miss.

Yes, they all apply; there's no "concealment bonus" or other reason the stacking rules would disallow it. You can either roll all of them sequentially or compute a single probability to make it faster, as long as you do the calculations right, but either way the percentages stack purely mathematically.

Irreverent Fool
2009-10-20, 07:32 AM
I think Blur does, at least with Mirror Image, as it's purely a visual effect. By stack, I mean your doubles also have a 20% miss chance, even if targeted.

This is incorrect. Blur affects creatures only. The illusions created by mirror image are not creatures but may be attacked as such. Curmudgeon has it right, as usual.

This is a common conception among players for the reason you stated. "It's purely visual". Granted, if you follow that route, displacement applies too. However, mirror image (http://www.d20srd.org/srd/spells/mirrorImage.htm) at no point says that the visual effects of spells on you has any effect on chance to hit the illusions with the exception of spells that render you invisible to the attacker.

But to answer the original question: Yes. Each miss chance is rolled separately. Mirror images just get checked first and if an image is targeted, it doesn't get any of your buffs.

obnoxious
sig

Random832
2009-10-20, 08:12 AM
Note that multiple miss chances are mathematically equivalent to a single miss chance equal to 1-∏(1-x), i.e. take the inverse of each miss chance [80 for 20, 70 for 30], multiply them all together [as percentages, i.e. 80%×70% = 56%, not 5600], and then take the inverse of the result [56% becomes 44%]

Keshay
2009-10-20, 08:15 AM
This is incorrect. Blur affects creatures only. The illusions created by mirror image are not creatures but may be attacked as such. Curmudgeon has it right, as usual.

This is a common conception among players for the reason you stated. "It's purely visual". Granted, if you follow that route, displacement applies too. However, mirror image (http://www.d20srd.org/srd/spells/mirrorImage.htm) at no point says that the visual effects of spells on you has any effect on chance to hit the illusions with the exception of spells that render you invisible to the attacker.

But to answer the original question: Yes. Each miss chance is rolled separately. Mirror images just get checked first and if an image is targeted, it doesn't get any of your buffs.

I think you're missing the point here, Blur or any other illusion would not be effecting the Mirror Images but the caster himself. Mirror Image states that:

"Enemies attempting to attack you or cast spells at you must select from among indistinguishable targets."

Meaning that the doubles look exactly like you. There is no caveat that if your appearance changes during the duration of Mirror Image that the doubless appearances do not change, they are always identical to the casters current appearance.

Blur's description states:

"The subject’s outline appears blurred, shifting and wavering. This distortion grants the subject concealment (20% miss chance)."

It specifically states that the visual distortion causes the miss chance. Since Mirror Image makes the doubles indistinguishable from the caster, this means the doubles also all have the save blurred outline, and therefore a miss chance. Otherwise, you'd just have the enemies targeting the blurry one, which would be contrary to the explicit description of Mirror Image that states the caster is indistinguishable from the doubles.

If, however, the miss chance was due to the character being partly incorporeal, then the Mirror Images would not get a miss%, due to the effect not being due to a visual effect. In this respect the distinction between Blur being a visual effect is a relevant factor in granting miss%.

ericgrau
2009-10-20, 08:19 AM
The problem with stacking most of these spells is that by the time you finish casting them the combat is over. I'd peg yourself with a greater invisibility and be done with it.

Myrmex
2009-10-20, 08:20 AM
(Greater) Mirror Image provides illusory doubles, but they go poof when struck. No other magical miss chances affect these doubles. Roll randomly to see whether a double or your person is targeted. Ghostform and Displacement stack on your person, though. Apply each miss chance sequentially.

Wouldn't some sort of obscuring affect, like fog, affect them? They are, after all, targets with AC.

Random832
2009-10-20, 08:23 AM
The problem with stacking most of these spells is that by the time you finish casting them the combat is over. I'd peg yourself with a greater invisibility and be done with it.

The idea for most of these exercises is that they're mostly relevant when you're powerful enough to be able to do all of these before combat or in the first round

PhoenixRivers
2009-10-20, 08:24 AM
Greater Blink is probably one of the most useful spells for this. Add in Mirror Image, and you'll have a rather potent defense...

Because in this instance, the Mirror images blink too.

Mirror image is <Personal>, with a target of You. That means wherever you are, so to is the effect.

Greater Blink sends you to the ethereal plane, and, when you're there, the Mirror images are too.

So, in effect, people can miss your mirror images.

ericgrau
2009-10-20, 08:39 AM
I think there was a FAQ entry on mirror image and blur. IIRC since blur is a visual effect it affects the images as well. EDIT: Yeup. Displacement works too, for the same reason.

Myrmex
2009-10-20, 08:42 AM
Greater Blink is probably one of the most useful spells for this. Add in Mirror Image, and you'll have a rather potent defense...

Because in this instance, the Mirror images blink too.

Mirror image is <Personal>, with a target of You. That means wherever you are, so to is the effect.

Greater Blink sends you to the ethereal plane, and, when you're there, the Mirror images are too.

So, in effect, people can miss your mirror images.

It's actually Personal; see text. It seems that once the spell is cast, they are no longer a personal spell on you, as they can be up to 5 from at least one other image.

Tyndmyr
2009-10-20, 08:53 AM
I've used blink + mirror image. We ended up ruling that it works on the mirrors, since they follow you, and you are blinking to the ethereal plane. They don't get the advantages of buffs on you, but they do get bonuses conferred by visibility/location.

Person_Man
2009-10-20, 08:57 AM
I'm aware that it's a house rule, but when I DM I only allow the highest miss chance to apply. My reasoning is that other similar magical effects don't stack (named bonuses, Enlarge Person and Expansion, etc) and, more importantly, full casters (the most powerful group) tend to abuse it the most.

Koeldflare, I personally know nothing about your DM or your gaming group, but I would suggest that you be mindful about making yourself nearly impossible to be hit unless you happen to be fighting the final BBEG of your campaign. Like other RAW but potentially game breaking rules (touch attacks, Greater Invisibility, Polymorph, etc) it's best to use them rarely, if at all.

Reaper_Monkey
2009-10-20, 09:17 AM
This is why Area of Effects were invented, I hope your stacking reflex saves too :smallamused:

Fluffles
2009-10-20, 09:25 AM
This is why Area of Effects were invented, I hope your stacking reflex saves too :smallamused:

Nah, I've got evasion for that :smallbiggrin:

Reaper_Monkey
2009-10-20, 09:36 AM
Nah, I've got evasion for that :smallbiggrin:

Touché. Very well... this calls for the age old crushing room! Nothing can evade a ceiling :smallbiggrin:!

Fluffles
2009-10-20, 09:38 AM
I can. I'm a ghost :smallbiggrin:

Curmudgeon
2009-10-20, 12:11 PM
Blur's description states:

"The subject’s outline appears blurred, shifting and wavering. This distortion grants the subject concealment (20% miss chance)."

It specifically states that the visual distortion causes the miss chance. Since Mirror Image makes the doubles indistinguishable from the caster, this means the doubles also all have the save blurred outline, and therefore a miss chance.

Blur
Illusion (Glamer)
...
Target: Creature touched
Yes, the Mirror Images are blurry, too, because that spell's description requires it. But that doesn't give the images a miss chance, because those images are not creatures. Blur only gives a creature a miss chance. Anything else would be exceeding the written rules.

If you need more than the RAW to work with, try this. Blurry Mirror Images aren't any harder to make some sort of weapon contact with, and that's all that's necessary to make them go poof. Blur make it harder to land a solid blow on an actual creature, where it could glance off armor or be dodged -- neither of which could happen with a Mirror Image.
The figments mimic your actions, pretending to cast spells when you cast a spell, drink potions when you drink a potion, levitate when you levitate, and so on.
...
Figments seem to react normally to area spells (such as looking like they’re burned or dead after being hit by a fireball). These figments have no capacity to try to dodge weapon blows.

Eldariel
2009-10-20, 12:11 PM
Touché. Very well... this calls for the age old crushing room! Nothing can evade a ceiling :smallbiggrin:!

I block the ground!

Keshay
2009-10-20, 01:12 PM
Yes, the Mirror Images are blurry, too, because that spell's description requires it. But that doesn't give the images a miss chance, because those images are not creatures. Blur only gives a creature a miss chance. Anything else would be exceeding the written rules.

If you need more than the RAW to work with, try this. Blurry Mirror Images aren't any harder to make some sort of weapon contact with, and that's all that's necessary to make them go poof. Blur make it harder to land a solid blow on an actual creature, where it could glance off armor or be dodged -- neither of which could happen with a Mirror Image. These figments have no capacity to try to dodge weapon blows.

Ignoring the relevant portion of an argument does nothing to refute it. It is specifically stated that the visual distortion generated by Blur is what grants the miss chance. It is specifically stated that the Mirror Images can not be differentiated from the caster by vision or hearing, therefore the images get a miss chance since the purely visual effect of Blur must be reflected in the appearance of the doubles in order for the spell description to be accurate. It does not matter that the Blur does not target the doubles, in this case the miss chance would be an effect of Mirror Image, not Blur.

Your argument is akin to saying that a Mirror Image would not reflect any changes made to the caster's appearance due to the casting of Alter Self, which certainly is not a reasonable argument.

And yes, blurry mirror images are harder to make weapon contact with, Blur states that the miss chance is granted by the visual distortion, which is then translated to the doubles. Neither spell mentions active attempts to dodge or Armor Class as being a constituent portion of the miss chance, so the abiltiy to dodge weapon blows is totally irrelevant to the discussion.

Natael
2009-10-20, 01:17 PM
What are some of the best ways to get some miss chances loaded up onto a melee character via (non-custom) magic items?

Glimbur
2009-10-20, 01:21 PM
What are some of the best ways to get some miss chances loaded up onto a melee character via (non-custom) magic items?

Minor Cloak of Displacement is like Blur all day, and arguably better than the Greater Cloak of Displacement because the greater one needs activation. It's core.

Keshay
2009-10-20, 01:30 PM
Potions of Blur and Displacement will work too. If you have UMD or a friendly caster, a Wand of Greater Invisibility will do wonders for you.

Sinfire Titan
2009-10-20, 01:35 PM
Touché. Very well... this calls for the age old crushing room! Nothing can evade a ceiling :smallbiggrin:!

Ha! There's so many counters to that trap that you may as well throw plush dolls at a brick wall.

Curmudgeon
2009-10-20, 02:11 PM
And yes, blurry mirror images are harder to make weapon contact with, Blur states that the miss chance is granted by the visual distortion, which is then translated to the doubles.
I won't try to refute your argument on the basis of the logic of different visual effects, because that isn't relevant here. The point that matters is that Blur only provides a miss chance to a creature, not a figment. The visual effect, a factor of Mirror Image, isn't pertinent to the restriction in the Blur spell's target. You can't get a miss chance from Blur for an invalid target, and Mirror Image doesn't provide a 1/n miss chance and an additional visual effect miss chance, because that's not afforded by the rules.

You can describe the visual effects any way you like. The miss chances do not stack if you obey the limits on each spell's capabilities.

Paulus
2009-10-20, 02:30 PM
I won't try to refute your argument on the basis of the logic of different visual effects, because that isn't relevant here. The point that matters is that Blur only provides a miss chance to a creature, not a figment. The visual effect, a factor of Mirror Image, isn't pertinent to the restriction in the Blur spell's target. You can't get a miss chance from Blur for an invalid target, and Mirror Image doesn't provide a 1/n miss chance and an additional visual effect miss chance, because that's not afforded by the rules.

You can describe the visual effects any way you like. The miss chances do not stack if you obey the limits on each spell's capabilities.

This is quite literally one of the oddest arguments I've seen.

Basically you are both right. Blur works because it blurs the character. Mirror image works because it creates duplicates of the original which look exactly alike. So if the individual used mirror image and blur, ... logically the original would be blurred and the mirror images would be too, since it would be illogical for the mirror images not to blur because then it would be pointless to be mirror images. Therefore, they should work together.

On the other hand, mirror images blurred or not, when struck by a weapon will disappear and no amount of blurring them should make a difference because they can be just as easily hit. Because it was intended as such that mirror image only allowed you to have doubles that dissipated when hit, which makes the miss chance, removing a copy each time- that is, auto hit them instead of hitting you- to make the spell at least fair on SOME level. After all, if the images can be missed to, most foes would stand even less of a chance. Therefore, it must work illogically in the name of balance. Or so it is intended, and is written.

Therefore, The images do indeed blur along with the original thereby not distinguishing the original from the copies, yet the rules say blur only works on a creature and will not work on a figment. Thus it only works on you but it LOOKS like it works on the mirror images, but they receive no miss chance because it was not intended as such and therefore the spell remains balanced. Therefore when a create strikes at you and misses purely by the greater miss chance with the stacking chances of blur and mirror image, a mirror image dissipates because that is what makes it a miss. They hit one of them instead of you, regardless if the blur helped or not. You still loose a mirror image, are still blurred, so the miss chances and visualizations stack but the mechanics remain the same, thus it is not a total stacking but one that still works together. Thus, you are BOTH correct, yet on different sides. This works and that works. As written as intended.

Keshay
2009-10-20, 02:36 PM
I won't try to refute your argument on the basis of the logic of different visual effects, because that isn't relevant here. The point that matters is that Blur only provides a miss chance to a creature, not a figment. The visual effect, a factor of Mirror Image, isn't pertinent to the restriction in the Blur spell's target. You can't get a miss chance from Blur for an invalid target, and Mirror Image doesn't provide a 1/n miss chance and an additional visual effect miss chance, because that's not afforded by the rules.

You can describe the visual effects any way you like. The miss chances do not stack if you obey the limits on each spell's capabilities.

I respect your strict interpretation of the rules as written, but as usual find the RAW to be incomplete and inadequate to describe all circumstances that may arise. In these cases a logical conclusion is acceptable to me and those I have played with. I agree to disagree.

/edit: AHHA! I see now. We have it backwards. You all are thinking that the miss chance is done first, that monsters always try to attack just the actual target, and that the images are an ablative kind of shield to be gotten through... That's not the case. An enemy has to choose which image to attack, hit its AC, then overcome the miss chance. Not, try to attack the PC, overcome the miss%, overcome AC, then overcome the MI.

Miss% is applied after AC, not the other way around.

Tyndmyr
2009-10-20, 02:41 PM
Well, no. You're working off the assumption that mirror images are intended to be automatically removed at a rate of 1/swing. They have their own AC, which does in fact receive your size and dex modifiers, lending credence to the idea that you modify the actual attributes of your images.

Thus, it's clear that effects on you DO modify the chance of your image being hit. Not all effects, sure, but it explicitly means that your images would inherit any AC bonuses through dex and size to you. The fact that it also explicitly says they exactly mimic you in appearance indicates they also gain the benefits or drawbacks of any special wholly visual effect. Specific examples are given, such as levitate when you levitate, but it's clear that this list is not exaustive.

Also, don't get hung up on the "they are images, not creatures" aspect. They are referred to as illusions, figments, images, and duplicates within the spell text alone. This indicates that these are all descriptive words, and not intended as a singular type. Also, images can be targetted by spells such as "hold person", albeit not intentionally, due to the randomization.

Paulus
2009-10-20, 02:48 PM
Really? I thought the miss chance provided by Mirror image was because of being more than one of you, thus when a baddie swung his sword and the miss chance came into play, it was because they swung at a duplicate instead of the real you, thereby removing the image in a 'slashed death' and missing you. And could fail in the same way if the baddie swung, and the miss chance did not prevail it actually hit YOU. Which goes to say, your AC and dex and what not all factor into the original hit YOU or NOT YOU. Therefore meaning if a monster swung and couldn't get past your dex, AC, AND miss-chance it instead still took out a mirror image of you because that was what made it miss.

And I assume that logically, since you had the miss chance on yourself from blur, this too factored in, and thereby when a swing missed YOU, it STILL took out a mirror image of you regardless because that is PART of what makes mirror image a miss chance. Being blurred makes your mirror images blurred too so it doesn't make you stand out from your images, but the miss chance is STILL based on the mechanics of the spell and the AC dex and such of YOU, NOT your mirror images. I've never heard of Mirror images having more or less hit chance before since I assumed they automatically went by whether or not the baddie hit YOU and if he didn't it was because he hit one of THEM.

fascinating!

EDIT:: of course one could go so far as to argue the opposite, and say that they DON'T stack because blurring yourself makes you stand out from your non blurred mirror images, thereby having only ONE of the miss chances apply (whichever ever was greater). So then I suppose the argument hinges on the fact of whether or not your mirror images take on the same exact visual effects as yourself.

And on another note, which spell you cast first, if you blur yourself first and THEN mirror image, it should work, but if you mirror image then blur yourself it doesn't.

My my, how odd!

jiriku
2009-10-20, 02:50 PM
Like the title implies, I'm wondering how certain spells that grant miss chances work with one another. Specifically I'm looking into the stacking effects of Displacement, Ghostform and Greater Mirror Image.

As a side note: is there any other spells that would stack with this combination? My character won't have a high AC so I'm looking into getting as many miss chances as possible.

I believe there is a 3rd-level spell by the name of shadow form in the Spell Compendium that will grant you additional miss chance.

Also, you may be interested in the 7th level wizzie spell project image (PHB). This creates an image of you that can actually cast spells. The image can cast illusion spells on itself, so it can benefit from mirror image, displacement, etc.

Tyndmyr
2009-10-20, 02:53 PM
Oh yeah, the randomization is completely seperate from the roll against AC.

We've got two members(including me) in one of my current games who stack high AC, blink, and mirror image in tough fights. It's pretty effective, but part of that is because the DM hasn't yet realized that blindfight is a great counter to mirror image, and AOEs/magic missiles are also great for thinning the image crowd down rapidly.

Various methods for gaining total concealment also work pretty good, too, but you need some way to still be able to get LOS/LOE to the target, and be aware that unless you move after casting, aiming at the center will still have a decent likelihood of targetting your square.

Lycanthromancer
2009-10-20, 02:55 PM
You could always get 100% concealment from any silent image spells you happen to have on hand. It's like mass invisibility but better!

Tyndmyr
2009-10-20, 02:56 PM
And on another note, which spell you cast first, if you blur yourself first and THEN mirror image, it should work, but if you mirror image then blur yourself it doesn't.

My my, how odd!

Nah, thankfully for the purposes of keeping track, the images replicate your appearance. If you appear to cast a spell, so do they. If you levitate, so do they. Thus, order shouldn't matter.

This makes a battlefield look terribly interesting when multiple people are using mirror image, btw.

Paulus
2009-10-20, 02:59 PM
Nah, thankfully for the purposes of keeping track, the images replicate your appearance. If you appear to cast a spell, so do they. If you levitate, so do they. Thus, order shouldn't matter.

This makes a battlefield look terribly interesting when multiple people are using mirror image, btw.

"Me me me."
"Me too."

Random832
2009-10-20, 03:03 PM
I wonder how the best way to handle mirror image combat with miniatures would be...

what i'm thinking is - each character with multiple images has a set of identical miniatures. Say, chess pawns.

The one that is the _real_ character has a sticker on the bottom.

When passing two images (or an image and real character) through each other, you pick them up off the grid, pass them behind your back, and set them down at the new locations.

Removing an image from the board requires it to be shown for inspection (that there is no sticker, and thus no "schrodinger" effect.)

Can anyone think of any flaws here?

jmbrown
2009-10-20, 03:04 PM
Also, don't get hung up on the "they are images, not creatures" aspect. They are referred to as illusions, figments, images, and duplicates within the spell text alone. This indicates that these are all descriptive words, and not intended as a singular type. Also, images can be targetted by spells such as "hold person", albeit not intentionally, due to the randomization.

Mirror image is a figment which can't produce a real effect. Spells create effects. While a mirror image will turn green if you do, it won't gain the benefit of an area effect spell that, say, grants a dodge bonus.

Mirror image will appear blurred but it's just as easy to hit as if it weren't. Before you attack you roll randomly to determine if you're hitting a real image or not. If you hit a figment, you roll; if you beat the AC, you destroy the image. If you don't beat the AC then nothing happens. Mirror image gains no special effects that you do because figments can't also be enchanted.

Keshay
2009-10-20, 03:24 PM
I wonder how the best way to handle mirror image combat with miniatures would be...

what i'm thinking is - each character with multiple images has a set of identical miniatures. Say, chess pawns.

The one that is the _real_ character has a sticker on the bottom.

When passing two images (or an image and real character) through each other, you pick them up off the grid, pass them behind your back, and set them down at the new locations.

Removing an image from the board requires it to be shown for inspection (that there is no sticker, and thus no "schrodinger" effect.)

Can anyone think of any flaws here?

Nothing so complex is necessary. No one is trying to deceive anyone else. You just plop down a few extra minis all around your guy, and when the DM announces attacks, the random determination is made whether its the real target, even if he chooses the "real" mini.

Attacks are made, Images hit go poof, and if the caster is hit he's "painted" untill his next action (if he moves, if he does not move, he's hosed).

Tyndmyr
2009-10-20, 03:32 PM
For things that involve "Pick the real one of x", it's useful to prevent metagaming, intentional or not. For mirror image, simply randomizing is sufficient.

However, they never really thought to specify...do you randomize between all images, as the text would seem to imply, even those out of range? What happens if you kill an image in the center of a conga line(now that you've broken the 5ft max seperation)? I've ruled that the out of range images poof when that happens, but it's certainly questionable.

Jmbrown, in D&D, just because something is an illusion/figment/etc doesn't make it "not a real effect". Illusions can have real effects on you. Other spells can sometimes have real effects on illusions. The example spells listed indicate that mirror image can gain status effects from spells you cast, specifically, levitate. If you move, the images are really moving, not just appearing to move. They certainly cannot be hit at the old location.