A good question arises from that - if our Wizard is standing on a pillar of rock, or on a narrow ledge, do some or all of the images appear standing in mid-air? If the caster is holding a pike, do some of his images appear impales upon it? They should each have a pike, I assume, as that would be attended gear.
Yes, if the caster is holding a weapon, so would the images. Would the be impaled? Only if the DM decides to functionally disallow the spell by being a jerk. The pike might pass through the square occupied by an image (or even the caster), but for the pike to impale an image, the caster would have to strike at it, making an attack. And, as we know, attacks pop images.
Fair enough. So if half the images are in front of the attacker and half are behind, why can't he tell whether the wizard casting a spell is in front of him or behind him?
Why are they behind the attacker?
I have to be standing somewhere. I may not even be able to get into range of some of those squares.
Unless the caster was standing right next to the attacker when the spell was cast, and the caster then failed to move (even a 5 foot step), there's no requirement that any of the images (or the original) be within striking distance of the attacker. The attacker would have to decide where to step up to, and where to strike.
And like I said, any caster who gives away his or her position deserves to get hit.
OK, let's assume we are arranged as follows (C = Caster, E = Enemy and I = Image):
W I I I I I I I I
E
Okay, so we're assuming that the images form a line, rather than the "cluster" described in the spell. With you so far...
The enemy can attack W, or one of the I's. Two questions:
(a) He guesses wrong and hits. Do all the other images further right dissipate? They are no longer within 5' of the caster or another image.
By your illustration, they're all within 5 feet of another image. They're just not within five feet of the caster. If the attacker has the Spellcraft to recognize the anomaly then they'll know that the caster, standing alone, has to be real.
(b) He misses. Can the Wizard take a 5' step, followed by a full round action, to rearrange the images as follows (the enemy, of course, not moving)?
..I I I I I I I I W
E
Are you asking if the caster can move 50 feet with a five foot step? I think the question answers itself. No. Or am I misunderstanding something?
Not bad - a 50' step! But he must be able to - he can rearrange everything to his liking, right? If he can't, a shuffle that puts an enemy back to a random roll seems pretty unlikely.
Okay, my question answered. Your example presumes an arrangement (a chorus line) that the spell description doesn't include. It talks about a "cluster", and never says that the caster has direct control, other than the chance to switch places with images. Also, I'm guessing that you're envisioning a wall at the left side of our text frame, so images couldn't shuffle past?
Oh, and the enemy can fly, but the Wizard and his images are standing along a 5' wide ledge, so they can't move out of that line structure.
Do you recall where I pointed out that the "roll randomly" part was the "general rule", not the universal/only rule? You're trying to invent scenarios where that general rule doesn't work. Which is why it's a general rule, not the universal/only rule.
Also, do you recall where I wrote that any interpretation of any spell can be shown to be invalid by someone concocting an unlikely scenario specifically designed to break the spell?
I actually meant that.
And when I said that the only way to avoid this was to get rid of all the spells, items, feats and non-real-world creatures?
Yeah, I meant that too.
So, having read what I wrote, you didn't have to go out of your way to prove me right. I mean, it's kinda nice that you did, but you didn't have to.
Let's think about the all-in-one-square interpretation, and a few of your own examples.
A wizard, holding a pike, casts
Mirror Image. Are at least some of the images impaled? If they were in separate squares they wouldn't have to be, but all crowded into one? A lot harder to envision them not being impaled, isn't it?
A caster with his entourage is standing on a ledge, facing an attacker who can fly. Attacker swings his spiked chain at the caster. How does he "hit" only one image? He can't have images dancing aside, there's no place for them to dance to.
Or forget the spiked chain. Any slashing weapon presents the same challenge. Attacker can be close enough to slash his scimitar or saber through the square, striking sparks along the wall behind as he goes, and leaving no chance that he won't at least touch-attack *something*. How does he "hit" only one image, if they're all in the same square? Not really possible, is it?
Any explanation can be taken apart by contriving the right circumstance. So do we just say that the spell can't work at all? That's kind of what's left, isn't it?
Alternately, what we're left with is that always unsatisfactory explanation of "Because it's magic".
But I'm curious: When the spell says the images "separate from you", how/why do you read that as "The images don't separate from you"? Why would the description emphasize that the images have to remain within five feet of each other, or the caster, if in fact they never get even three feet from the caster, and remain in his/her square? Why not just write, "The images all stay with the caster"?
The spell says they separate. The description says they stay in a cluster, with none being more than one square (five feet) away from another image, or the original. It doesn't say that they don't separate, or that they remain with the caster.
Does that separation allow images to share squares with each other, or the original? Well, for the "pass through one another" aspect, they'd have to be able to. Which also means that they don't perfectly mimic the caster's actions all the time. If they did, they couldn't change places. Image has to move left while caster moves right at some point.
Now what happens if the caster throws a dagger? All the images throw daggers, naturally. Do all of the daggers converge on the single target? Or, once in the air, do the duplicates disappear. They're no longer attended objects, after all.
Treating it like science, they should disappear. The spell shouldn't cover them.
Treating it like magic, which works "the way it's supposed to", you'll see daggers converging on a target, to hit or miss together at that point.
So let the spell work "the way it's supposed to". Don't try to dissect it. Don't try to logic it apart. Play it as written, and get on with the game.