Magic Missile and Empowered Evocation in 5.5e

Hi all, I'm struggling to understand a specific interaction with the magic missile spell and the evocation wizard's level 10 subclass feature, empowered evocation (hopefully this is the right place). As far as I can tell, one of two things happen:

1. Roll 1d4+1 that counts for all darts, then add the intelligence modifier to each. So (e.g.) with a +4 intelligence modifier rolling a 2 on the d4 each dart would do 2 + 1 + 4 = 7 damage for each missile

2. Roll 1d4+1 for each dart, adding the intelligence modifier to one dart. So (e.g.) casting at level 1 with a +4 intelligence modifier, there would be two darts doing 1d4 + 1 damage (separate rolls), and one dart doing 1d4 + 1 + 4 damage (another separate roll)

The text of magic missile says

"You create three glowing darts of magical force. Each dart strikes a creature of your choice that you can see within range. A dart deals 1d4 + 1 Force damage to its target. The darts all strike simultaneously, and you can direct them to hit one creature or several." [PhB 2024 p295, emphasis mine]

And empowered evocation says

"Whenever you cast a Wizard spell from the Evocation school, you can add your Intelligence modifier to one damage roll of that spell."

For 5e, as far as I can tell the first case is what happens (one roll, but the intelligence modifier applies to all of them) because the darts hit simultaneously: "If a spell or other effect deals damage to more than one target at the same time, roll the damage once for all of them." [PhB 2014 p196, emphasis mine]

This text isn't in the 5.5e PhB, all I can find is 

"Damage against Multiple Targets

When you create a damaging effect that forces two or more targets to make saving throws against it at the same time, roll the damage once for all the targets. For example, when a wizard casts Fireball, the spell’s damage is rolled once for all creatures caught in the blast." [PhB 2024 p28]

... but magic missile doesn't have a saving throw so it doesn't apply. Then in the 'Damage Rolls' section it says...

"Each weapon, spell, and damaging monster ability specifies the damage it deals. You roll the damage dice, add any modifiers, and deal the damage to your target. If there’s a penalty to the damage, it’s possible to deal 0 damage but not negative damage.

When attacking with a weapon, you add your ability modifier—the same modifier used for the attack roll—to the damage roll. A spell tells you which dice to roll for damage and whether to add any modifiers. Unless a rule says otherwise, you don’t add your ability modifier to a fixed damage amount that doesn’t use a roll, such as the damage of a Blowgun. See chapter 6 for weapons’ damage dice and chapter 7 for spells’ damage dice." [PhB 2024 p27, emphasis mine]

... which just tells me to look at the spell description, so I have no idea 😅. Any help would be greatly appreciated! 

"Simultaneously" is irrelevant. 

Each dart is a separate instance of damage. Empowered Evocation very specifically allows you to add your INT modifier to one damage roll. Only 1 dart is affected.

If you cast fireball, and affect 6 enemies, you would damage them all "simultaneously", too. You would still only get to add your INT modifier to one of those rolls. 

Empowered Evocation allows you to deal extra damage equal to your INT modifier to one target once per spell, period. 

Whether to roll 1d4 and have that one roll be the same damage for all the magic missile darts or to roll a handful of d4 dice appropriate to the number of darts for the spell level you're casting Magic Missile at has been a point of contention in some circles for a while now.

I've always favored rolling a handful of d4's, mostly because it feels nice to toss a big handful of dice. But I just made a new Wizard on DDB and bumped them up to level 20. I looked at how DDB handles dice rolling on Magic Missile and other spells like Fireball, and how it handles them when they're upcast. With Fireball, DDB rolls a bunch of D6's, and increases the number of dice when upcast. But with Magic Missle, it only rolls 1d4, no matter what level you cast MM at.

So... it looks like Magic Missile is just a single 1d4 roll, and if something applies a bonus to a single roll, it applies to all the darts.

2014 rules was roll once and all darts do that damage so empowered evocation affected all darts. This was confirmed in Sage Advice.

2024 rules however no longer has the line that made that interaction clear. So, up to DM interpretation. 

Quote from WishIHadACleverUsername>>

[...] For 5e, as far as I can tell the first case is what happens (one roll, but the intelligence modifier applies to all of them) because the darts hit simultaneously: "If a spell or other effect deals damage to more than one target at the same time, roll the damage once for all of them." [PhB 2014 p196, emphasis mine]

 I think that, due to that 5e rule, Magic Missile was ruled (though I'm not sure if everyone agrees) the way the Dev suggested and Cyb3rM1nd mentioned.

@BrailSays So Scorching Ray gets +X 1 time per cast,but Magic Missile gets +X on every bolt?
@JeremyECrawford Correct. Magic missile is an oddball, in that it functions a bit like an area-damage spell ("strike simultaneously").

 
And:

@BrailSays Could we please get an official RAW ruling on +damage to Magic Missile/etc? Very heated debate about it on the reddits 
@BrailSays +x per bolt,even on same target?
@JeremyECrawford Yep. It's one damage roll, just like fireball, but that roll can damage the same target more than once.

Quote from WishIHadACleverUsername>>

[...] This text isn't in the 5.5e PhB, all I can find is 

"Damage against Multiple Targets

When you create a damaging effect that forces two or more targets to make saving throws against it at the same time, roll the damage once for all the targets. For example, when a wizard casts Fireball, the spell’s damage is rolled once for all creatures caught in the blast." [PhB 2024 p28]

... but magic missile doesn't have a saving throw so it doesn't apply. [...]

 Now the rule only applies to saving throws, so it doesn't apply to Magic Missile.

This should be the right ruling then:

Quote from WishIHadACleverUsername >>

[...] 2. Roll 1d4+1 for each dart, adding the intelligence modifier to one dart. So (e.g.) casting at level 1 with a +4 intelligence modifier, there would be two darts doing 1d4 + 1 damage (separate rolls), and one dart doing 1d4 + 1 + 4 damage (another separate roll) [...]

To me magic missile clearly requires a separate roll for each dart.

The Evo bonus adds INT mod to one of them.

I certainly understand why you’d want it to go to each one.

The issue with your “more than one target” interpretation is it treats magic missile as an area of effect spell which it is not.

But again you identified a very important change from 2014 to 2024 that is worth thinking about for other spells.