Welcome changes to this spell.  Triggering on when you're hit instead of when you're targeted means the images are always useful, and a high AC caster won't be wasting images on attacks that would miss them anyways.

The math for whether an image is targeted instead of the caster also works more in the caster's favour.  Previously it was (roughly representing) 3/4, 2/3, 1/2 odds of hitting an image instead of the caster if they had three, two, or one image remaining.  Now it's 7/8, 3/4, 1/2 for three, two, and one images.

Those odds are assuming a roll of 4 or higher on any of the d6's. In reality, the chances of hitting a duplicate is insanely higher now. For 3, 2, and 1 duplicate, the odds of hitting a duplicate are 2/3 (66.7%), 11/12 (91.7%), and 26/27 (96.3%) respectively. 

IMO, it's a weird change. The original made since. The odds roughly represented the chances that an attacker would target a duplicate. The duplicate AC was redundant in the original, but the odds for targeting made more sense. 

It seems like, either they made a mistake, or not a lot of thought was put into it. 

 Question for this spell!!

does a creature with tremorsense are unaffected ?? 

Do images change if your appearance changes?  

Hypothetical 1. Suppose you cast mirror image, and then cast Change Self to look like another party member.  

Hypothetical 2. Suppose you cast  mirror image, and then cast Polymorph to actually become a T-Rex.   

Why not just close your eyes and attack the wizard with disadvantage instead? Probably a better chance of hitting.

Wish it was a ba

Stacks nice with defensive dualist

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Quote from DrDeadPasta >>

Those odds are assuming a roll of 4 or higher on any of the d6's. In reality, the chances of hitting a duplicate is insanely higher now. For 3, 2, and 1 duplicate, the odds of hitting a duplicate are 2/3 (66.7%), 11/12 (91.7%), and 26/27 (96.3%) respectively. 

IMO, it's a weird change. The original made since. The odds roughly represented the chances that an attacker would target a duplicate. The duplicate AC was redundant in the original, but the odds for targeting made more sense. 

It seems like, either they made a mistake, or not a lot of thought was put into it. 

 Yeah, I've got to think they misworded this, it should be 4 or higher. As you said, the chances of hitting a duplicate are insanely higher now. I believe you miscalculated on the middle one, the odds are 32/36=8/9=88.88%. Still absolutely nuts.
I think they didn't want to have people have to memorize/(keep looking up during combat) the different numbers for the different remaining duplicates. But yes, the old percentages made sense, these new percentages don't make sense. Even doing 4 or higher they don't really make sense. I guess you could justify the 4 or higher percentages by saying the duplicates make some effort to intercept for you. The 3 or higher percentages are so insanely high there's no justifying them.

I would have changed it so the illusion has sound & temperature and so fools blindsight, and it's effect is disadvantage on attacks until 4 misses occur during that minute. Much simpler, and differentiates it from Blur.

Though I appreciate the simplification of having to hit the target first ...

I much prefer the old and simple way it worked in 2e and 3e, where you just rolled an equal or random chance ...  The old rule did not even explain which dice to roll and it presumed DMs were intelligent enough to figure 1d4 (or 1d8) if there are 3 images+1 real, 1d6 if 2 images+1 real, etc. 

The above classic method means you roll one dice instead of the one dice for every image in this 2024 version. 

Anyhow, that is a possible and easy homebrew idea. 

Mmm d6s

Shame there isn't an "At Higher Levels" feature for the spell for additional duplicates. Casting an un-scaling 2nd level spell with a Warlock's 5th level pact slot is a pretty big whiff.

So I'm correct to assume a fireball does not hit these mirror images?

Quote from Matiej >>

So I'm correct to assume a fireball does not hit these mirror images?

 

 

Correct. The spell description says "each time a creature hits you with an attack roll", and fireball doesn't use an attack roll.

Only effects attack rolls. Fireball, although aggressive, is not an attack roll spell. So you are correct. However, you still have to make a dex saving throw.

If you had mirror image and fire shield activated at the same time, with the rewording of the mirror image spell to say each time a creature is hit instead of targeted, would the attacker get damaged by the fire shield when the image is destroyed since it is considered a hit?

Quote from Edude711 >>

If you had mirror image and fire shield activated at the same time, with the rewording of the mirror image spell to say each time a creature is hit instead of targeted, would the attacker get damaged by the fire shield when the image is destroyed since it is considered a hit?

No, I don't think so. Fire Shield only triggers if you are hit with an attack. This spell says the duplicate is hit instead of you, meaning you aren't being hit, meaning Fire Shield doesn't trigger.

If an illusionist casts mirror image on himself in round 1 and then invisibility on himself in round 2, are the 3 mirror images invisible or visible?

Quote from ERuthruff >>

If an illusionist casts mirror image on himself in round 1 and then invisibility on himself in round 2, are the 3 mirror images invisible or visible?

There's nothing in the spell description that says that the mirror images change their appearance when the caster's appearance changes, so I think RAW they don't. And therefore they don't become invisible in this scenario.

I think, however, there's an argument that this spell shouldn't be effective if you're invisible, since it says it doesn't work on creatures with the Blinded condition. You having the Invisible condition isn't quite the same thing, but the spirit of the rule here appears to be that it doesn't work if the attacker can't see you.

Really wish you could upcast it. Previously it was impossible without making extra, now it's really easy so really wish you could upcast.

One per lvl probably too much, but one per two?