Various text
So, from
mirror image:
Enemies attempting to attack you or cast spells at you must select from among indistinguishable targets. Any successful attack against an image destroys it.
(Bold emphasis added.)
From magic missile:
Targets: Up to five creatures, no two of which can be more than 15 ft. apart
...
A missile of magical energy darts forth from your fingertip and strikes its target, dealing 1d4+1 points of force damage.
...
Inanimate objects are not damaged by the spell.
Based on the spell text, I'd rull that since magic missile is a "spell targetting the caster", the mirror image text requires the caster select an image at random for each missile. This is based on a read which is that the *caster* selects the target, and the missile unerringly strikes that target. It's up to the caster to pick the target, not the spell.
However, at that point, the text is ambiguous. Since magic missile can only target creatures, does the magic missile fizzle, or does it strike, but deal no damage? This is important because one must decide if the missile is considered a
successful attack. I consider the text to be ambiguous because the targetting line disallows non-creatures from being targetted, but then goes on to say that inanimate objects are not damaged by the spell. I get a disconnect between 'up to 5 creatures' and 'inanimate objects'. If the text had "
cannot damage an inanimate object", then I don't have a problem, but the text reads "
are not damaged".
Now, I'm wondering now about the text from invisibility:
For purposes of this spell, an attack includes any spell targeting a foe or whose area or effect includes a foe. (Exactly who is a foe depends on the invisible character’s perceptions.)
If one were to case magic missile while invisible, and have the misfortune to select one of the figments from mirror image, does one become visible? Is a figment a foe? Does a figment count as a foe because you think that it is? What if you know that it isn't because another attack in the round has given you accurate targetting information?
For multiple missiles (and generally for spells with multiple targets), I thought that the targetting rules were handled separately for each target. I'm not sure if the the targetting is done all at once, or one at a time, since I've seen GM's do this either way.
In any case, I thought that magic missile was grandfathered to remove figments, one per missile, although, I don't see that on
www.d20srd.org.