D&D 5E How does Mage Slayer feat reaction attack sequence with the spell effects of the triggering caster?

[Seramus]

It happens after, which is bad if they are blasting you or hitting you with CC. But it's GOOD for interrupting concentration since that also starts after the spell is cast (including if they ready an action to cast).

 

[bedir than]

It happens after, which is bad if they are blasting you or hitting you with CC. But it's GOOD for interrupting concentration since that also starts after the spell is cast (including if they ready an action to cast).

Let's say they fireball the Mage Slayer character and that drops them to 0.
At my table I would likely allow the the Reaction attack to still work, because that seems cinematic, to me

 

[Scott Christian]

Page 193 says it's after, or you skip your chance.

Xanathar's and the DMG say it's after, unless the effect specifies otherwise.

Which is definitely a bummer for Mage Slayer, since it doesn't specify. I may house rule that.

You are right. Sorry about that. I think they should have written that as two sentences. I was looking at it as a reaction, such as: "I cast magic missile if the wizard casts shield." Then prior to the wizard casting shield (in game the PC sees the wizard start), then the PC lets loose the magic missile. Thanks for making me review this. It is appreciated.

 

[Stoutstien]

You are right. Sorry about that. I think they should have written that as two sentences. I was looking at it as a reaction, such as: "I cast magic missile if the wizard casts shield." Then prior to the wizard casting shield (in game the PC sees the wizard start), then the PC lets loose the magic missile. Thanks for making me review this. It is appreciated.

It's a common misread because it doesn't make any sense so it goes under the radar for a lot of tables.

Not necessarily a bad thing. Nothing worse to see the look on a player's face when you tell them that that really cool but relatively weak thing that they were excited about doesn't work the way they wanted to because of rules.

The wording of the monster hunter ranger is more on point of the theme of this feat.

 

[Bacon Bits]

I'd be inclined to rule that it's dynamically whatever benefits the character with Mage Slayer the most, or, alternately, the player's choice. That means if they cast Misty Step or Teleport, then the attack happens before the caster disappears. If they cast Bless or Wall of Fire, then they will need to make a concentration save at disadvantage if they're hit. If they cast Invisibility or Polymorph, they choose whether they want to strike before the spell completes (and before any benefits) or after it completes (and potentially disrupting concentration).

It's a very narrow feat, so it should be quite punishing when it actually comes up.

That said, I've got little interest in blind adherence to RAW, and that tends to make a lot of people online extremely anxious.

 

[TheSword]

Being able to force a concentration check on a spell that has just been cast with disadvantage on the check is still very good. Considering that it’s a free attack out of your turn.

Sure fireball could be the spell cast but how often is an 8d6 fireball going to make that much difference on a single melee PC. Particularly when Mage Slayer is giving you advantage on the save.

 

[billd91]

The DMG says,

"Typical combatants rely on the opportunity attack and the Ready action for most of their reactions in a fight. Various spells and features give a creature more reaction options, and sometimes the timing of a reaction can be difficult to adjudicate. Use this rule of thumb: follow whatever timing is specified in the reaction’s description. For example, the opportunity attack and the shield spell are clear about the fact that they can interrupt their triggers. If a reaction has no timing specified, or the timing is unclear, the reaction occurs after its trigger finishes, as in the Ready action."

This is the important clue, along with the opportunity attack description in the Players Handbook. There, it describes just the OA caused by movement, but it clearly indicates that it comes before the creature leaves the reach of the opportunity attacker. The DMG indicates that, unless other timing is specified, opportunity attacks interrupt their triggers. So the mage slayer does get to attack the caster trying to misty step away. That, however, doesn't mean the casting is disrupted. It just means that the misty step or dimension door or other insta-disappear spell doesn't protect the caster from that parting shot from the mage slayer.

 

[Mannahnin]

This is the important clue, along with the opportunity attack description in the Players Handbook. There, it describes just the OA caused by movement, but it clearly indicates that it comes before the creature leaves the reach of the opportunity attacker. The DMG indicates that, unless other timing is specified, opportunity attacks interrupt their triggers. So the mage slayer does get to attack the caster trying to misty step away. That, however, doesn't mean the casting is disrupted. It just means that the misty step or dimension door or other insta-disappear spell doesn't protect the caster from that parting shot from the mage slayer.

Point of order- does Mage Slayer actually say it's an opportunity attack? My recollection is that it does not. It says you can make an attack as a reaction, but doesn't call it an opportunity attack.

 

[billd91]

Point of order- does Mage Slayer actually say it's an opportunity attack? My recollection is that it does not.

It does not, but if it walks like a duck, etc... I'm comfortable calling it a duck.

 

[Mannahnin]

It does not, but if it walks like a duck, etc... I'm comfortable calling it a duck.

I'm definitely not. They have the terminology "opportunity attack" available and didn't use it.

I'd certainly consider house-ruling the feat to make it one, though.