Are dragon breath attacks magical? Is Mind Blast and Devour intellect spell casting

[stenver]

My players got hold of the Armor of Invulnerability. I was wondering if they are invisible vs dragons now?

My player got hit with Devour intellect, but had mage slayer feat. I ruled that it was not a spell casting and he cannot make a reaction attack. Was i mistaken?

[TheOOB]

For the first one, assuming you mean invincible, I'd probably count it as magical. To my knowledge there isn't any clear line between magic and non magic damage, but dragons and their abilities are clearly supernatural(and non magical fire does pretty pathetic damage)

On the other hand, spells are very specific things, if a monster can cast spells it will have the spellcasting or innate spells feature(or possibly pact magic). An other abilities are not spells unless they say otherwise.

[Inevitability]

Doesn't the Armor specifically point out it works against nonmagical weapon attacks?

[stenver]

For the first one, assuming you mean invincible, I'd probably count it as magical. To my knowledge there isn't any clear line between magic and non magic damage, but dragons and their abilities are clearly supernatural(and non magical fire does pretty pathetic damage)

Interesting.. but by that logic i could say that any monster attack is magical if i deem it to be so.. It seems a bit sketchy


Doesn't the Armor specifically point out it works against nonmagical weapon attacks?

Nope:


ARMOR OF INVULNERABILITY
Armor (plate), legendary (requires attunement)
You have resistance to nonmagical damage while you wear this armor. Additionally, you can use an action to make yourself immune to nonmagical damage for 10 minutes or until you are no longer wearing the armor. Once this special action is used, it can't be used again until the next dawn.

[Notafish]

My players got hold of the Armor of Invulnerability. I was wondering if they are invisible vs dragons now?

My player got hit with Devour intellect, but had mage slayer feat. I ruled that it was not a spell casting and he cannot make a reaction attack. Was i mistaken?

I think it's up to you whether or not dragon breath is magical. I would say that it is not -- dragons aren't getting their breath powers by tapping into the weave or whatever, they have fire breath because they are dragons and their insides create fire/lightning/etc. If a spellcasting dragon cast a fireball spell, on the other hand, I don't think that I could effectively argue that it wasn't a magical damage source.

With the Intellect Devourer, the Devour Intellect power is unique, but it is not spellcasting -- the monster should have the "Spellcasting," "Innate Spellcasting," or "Psionics" feature and a list of spells if it is a spellcaster. I agree with your ruling.

[Notafish]

I'd imagine that most adult dragons would be clever enough to figure out why the guy in the fancy armor isn't being damaged by their attacks, though. Hopefully the party only has one suit of Invulnerability armor?

[stenver]

Yes only 1 suit. It was an epic adventure to get it at level 4 in black dragons lair. But when they met the dragon, the woman wearing the armor got cold feet and ran away. Others were forced to run as well, while 1 remained behind to sacrifice himself and buy others time to run.

Thanks for everybody's input! I think im just going to make it magical when a dragon get old enough, like adult. Before that the dragon has not yet fully unlocked the powerful seeds of his ancestries magic.

[Kryx]

Tweets on this topic:

@mikemearls SU abilities not in 5E. Does that mean breath weapons(dragon,mephit) and infernal wounds work in anti-magic field? up to the DM?

@jaceimba DM can feel free to rule otherwise - I believe description of ability should specify if it's a key issue.


@JeremyECrawford Is dragon breath a magical effect? Magical effects are not clearly defined in 5E. It implies dragon's are magical creatures

@Aseahawkfan A monster ability is magical if it involves a spell, is a spell attack, or is described as magical (e.g., Change Shape).

So the answers: Dragon's Breath and Devour Intellect are not magical. Mind Blast as well.