Concentration Spell + Shifting Planes.

[Tawmis]

So - say there's a monster that can cast a concentration spell (let's say Faerie Fire) and as a bonus action, it can magically shift from the Material Plane to the Ethereal Plane, or vice versa.

So it casts Faerie Fire, bonus actions to shift to Ethereal - with the intention next round - of coming back to Material.

Due to Concentration not being broken - does the spell still hold (say someone failed their Dex save) - when the creature teleports back magically to the Material Plane the following round?

Or does shifting planes break it?

[Valmark]

Shifting planes doesn't break Concentration on spells ^^

[Chronic]

I'm not sure there is an explicit answer in the rules on this subject. And if I'm not wrong about it, it would mean that concentration spell should keep working across planes if not otherwise specified. You could justify a DC 10 concentration check as per the rules about environmental effect.
Outside of Raw I think you could rule it as you want and it would be easy to justify going either ways.

[Ionathus]

As others have said, there's not much clear guidance here.

I would probably rule that this combo is allowed for plane shifting under your own power, but your concentration is threatened if someone else does it to you. Chronic's point about environmental effect makes logical sense: suddenly being in a different plane of reality would certainly be a disorienting experience.

And in the case of the 4th level spell Banishment, the concentration-breaking is fully RAW: the demiplane imposes the incapacitated condition, which breaks concentration.

[Valmark]

And in the case of the 4th level spell Banishment, the concentration-breaking is fully RAW: the demiplane imposes the incapacitated condition, which breaks concentration.

Eh, kinda. I'd say it's not the plane-shifting but the spell that does it, since normally planes/demiplanes you can travel to don't incapacitate you.

[Tawmis]

Thank you! I am of the same mine - that this would work.

Essentially it's for a Homebrew Monster (post in the forum over here) that is essentially a Drider with a Phaser Spider's body - giving it the Phaser Spider's ability to go Material/Etheral Plane as a Bonus action.

And I thought, if it cast Faerie Fire on it's turn, bonused to Etheral, then on the next round, bonus to come back to Material, next to someone who was glowing - it'd be a dangerous (and easy) way to avoid "Attacks of Opportunity" if it's looking to melee someone who was glowing from Faerie Fire.

[Chronos]

My table rules that you can't concentrate on an effect on another plane. But in this specific case, a monster that inherently has both abilities, I would be inclined to make an exception. If you feel you must justify it, then just give them an ad-hoc extra ability that says "The phase drider can concentrate on a spell on the material plane from the ethereal plane, or vice-versa".

[Lunali]

Eh, kinda. I'd say it's not the plane-shifting but the spell that does it, since normally planes/demiplanes you can travel to don't incapacitate you.

Agreed, the same spell when applied to an extra planar creature would send them to another plane while allowing them to act freely. Banishment also demonstrates that being on a different plane from your target does not normally break concentration. It is possible that being on a different plane would trigger range limitations specific to the spell, for example if you used compelled duel then shifted to the ethereal plane, the compelled duel would end even if you were "next to" the target.

[Ionathus]

Eh, kinda. I'd say it's not the plane-shifting but the spell that does it, since normally planes/demiplanes you can travel to don't incapacitate you.

...which is why I said "the demiplane" instead of "any demiplane." This specific demiplane is a unique feature of this spell, for creatures who are native to the current plane and have nowhere else to be banished to.

[Valmark]

...which is why I said "the demiplane" instead of "any demiplane." This specific demiplane is a unique feature of this spell, for creatures who are native to the current plane and have nowhere else to be banished to.

I know- I was just noting that it wasn't the plane-shifting that provoked the incapacitation, which is what the OP was interested in, but rather the spell.

[Keravath]

The rules are actually pretty clear. They explicitly list the things that break concentration on a spell.

"Normal activity, such as moving and attacking, doesn't interfere with concentration. The following factors can break concentration:
• Casting another spell that requires concentration. You lose concentration on a spell if you cast another spell that requires concentration. You can't concentrate on two spells at once.
• Taking damage. Whenever you take damage while you are concentrating on a spell, you must make a Constitution saving throw to maintain your concentration. The DC equals 10 or half the damage you take, whichever number is higher. If you take damage from multiple sources, such as an arrow and a dragon's breath, you make a separate saving throw for each source of damage.
• Being incapacitated or killed. You lose concentration on a spell if you are incapacitated or if you die."

The DM might also decide that certain environmental phenomena, such as a wave crashing over you while you're on a storm-tossed ship, require you to succeed on a DC 10 Constitution saving throw to maintain concentration on a spell."

That's it. Nothing else in the rules breaks concentration. The DM could decide to impose other constraints on concentration but it would be a house rule.

On the environmental front, someone who took damage as a result of plane shifting (e.g. plane of fire without fire resistance/immunity) would need to check to see if they maintained concentration. However, there is NO requirement to be on the same plane in order to maintain concentration on a spell.

[Ionathus]

The DM might also decide that certain environmental phenomena,

This is what some of us are saying: that "suddenly on a different plane of reality" would qualify as "environmental phenomena". *I* would certainly be as distracted by that as by a large wave crashing down on me!

[Tawmis]

Yeah - like if someone plane shifted the caster who was concentrating - I could see that as a distraction.

But since the creature in question can plane shift themselves - and cast - I'd assume they maintain concentration, because this is like chewing bubble gum and walking - a part of every day life for them.

And probably a common tactic - "Faerie Fire, bonus plane shift" - next round, "bonus plane shift back, next to someone glowing - make an attack at advantage" (should they wanna melee) - or just plane shift back, at the perfect maximum distance to longbow without disadvantage (or even with disadvantage, since the Faerie Fire would cancel that out and make it a normal attack roll).

Potentially such a deadly combo.

[Lunali]

This is what some of us are saying: that "suddenly on a different plane of reality" would qualify as "environmental phenomena". *I* would certainly be as distracted by that as by a large wave crashing down on me!

I wouldn't classify suddenly being on a different plane as something to potentially break concentration on its own unless it was completely by surprise (as in, outside of combat or while the target is surprised in combat without the target realizing the spell was being cast). Now it is entirely possible that something about the new plane would qualify, such as finding yourself suddenly neck deep in the plane of water, assaulted by the howling winds of pandemonium, or even just floating somewhere in the astral plane.

[Chronos]

The rules don't really support a change of plane breaking concentration. When a table rules that, it's more for reasons of immersion or thematics. When you cast a concentration spell, there's some sort of magical connection between you and the target of the spell (as evidenced by the fact that something happening to you can have an effect on the spell, namely ending it). It seems odd that hitting a spellcaster on one plane could cause something to happen on another plane, especially when the spell involved is a low-level one.

So the houserule is that the change of plane itself disrupts that magical connection, with the effect of ending the spell.

[Tawmis]

The rules don't really support a change of plane breaking concentration. When a table rules that, it's more for reasons of immersion or thematics. When you cast a concentration spell, there's some sort of magical connection between you and the target of the spell (as evidenced by the fact that something happening to you can have an effect on the spell, namely ending it). It seems odd that hitting a spellcaster on one plane could cause something to happen on another plane, especially when the spell involved is a low-level one.
So the houserule is that the change of plane itself disrupts that magical connection, with the effect of ending the spell.

So how do you rule an enemy casting Faerie Fire (being in range of casting the spell - 60') - it lands on a target who fails to save.
The caster then spends the next three turns dashing away (avoiding being hit) while minions keep the target busy.
So now, the caster (let's say was at 60' exactly - has now spent three turns dashing - so, let's say 60' each time - so that's 60'+180' = 240' from the target).
Now the caster can't see the target - would that interrupt the spell? Since it can technically go 1 minute (concentration).

Because shifting planes as a bonus action, then coming back as a bonus action on it's next turn is technically happening fairly quickly (in game mechanics, if each round is 6 seconds).

Not arguing - I am just curious how you'd handle the situation of a caster who hits the spell - then spends every action bolting away (avoiding being hit) vs a caster who hits the spell, steps away as a bonus, comes back next round as a bonus.

[Rukelnikov]

The rules don't really support a change of plane breaking concentration. When a table rules that, it's more for reasons of immersion or thematics. When you cast a concentration spell, there's some sort of magical connection between you and the target of the spell (as evidenced by the fact that something happening to you can have an effect on the spell, namely ending it). It seems odd that hitting a spellcaster on one plane could cause something to happen on another plane, especially when the spell involved is a low-level one.

So the houserule is that the change of plane itself disrupts that magical connection, with the effect of ending the spell.

I understand what motivates such a houserule, but how do you rule offensive banishment then? Is it a feature specific of that spell that allows it to bypass such limitation?

[Keravath]

So how do you rule an enemy casting Faerie Fire (being in range of casting the spell - 60') - it lands on a target who fails to save.
The caster then spends the next three turns dashing away (avoiding being hit) while minions keep the target busy.
So now, the caster (let's say was at 60' exactly - has now spent three turns dashing - so, let's say 60' each time - so that's 60'+180' = 240' from the target).
Now the caster can't see the target - would that interrupt the spell? Since it can technically go 1 minute (concentration).

Because shifting planes as a bonus action, then coming back as a bonus action on it's next turn is technically happening fairly quickly (in game mechanics, if each round is 6 seconds).

Not arguing - I am just curious how you'd handle the situation of a caster who hits the spell - then spends every action bolting away (avoiding being hit) vs a caster who hits the spell, steps away as a bonus, comes back next round as a bonus.

A creature can run as far as it likes. CASTING a spell has a certain range but for most spells, once cast, there are no range requirements. You can cast a concentration spell and then teleport 1000 miles away and still continue concentrating on it. The ONLY conditions that break concentration are the ones I cited in an earlier post. Anything else is a house rule.

For some folks .. having magic cross planes is something they seem to have trouble with even though spells like Banishment allow the caster to send the target to another plane and continue to concentrate on the magical effect that affects a creature on another plane. RAW there is no issue with continuing concentration from another plane. Neither being on another plane nor yet act of changing planes explicitly breaks concentration.

[Chronos]

Obviously Banishment or the like still works, because that's what it does. There's no dissonance with a spell crossing planar boundaries, when crossing planar boundaries is exactly what the spell is designed to do. It takes a lot more suspension of disbelief to accept something like Faerie Fire maintaining an interplanar connection, though.

And I've already stated that I'd also make an exception for a case like the OP's phase drider, for which shifting planes (at least, two particular planes) is as natural as breathing. There, it's not the Faerie Fire that's providing the interplanar connection, but the monster's own inherent phasiness.

[Valmark]

Obviously Banishment or the like still works, because that's what it does. There's no dissonance with a spell crossing planar boundaries, when crossing planar boundaries is exactly what the spell is designed to do. It takes a lot more suspension of disbelief to accept something like Faerie Fire maintaining an interplanar connection, though.

Only if you consider "interplanar connections" to be more complicated. In every game who establishes what's what is the DM, so concentrating on Faerie Fire from a different plane being any harder then eating a sandwich is completely up to the DM.

[Keravath]

Obviously Banishment or the like still works, because that's what it does. There's no dissonance with a spell crossing planar boundaries, when crossing planar boundaries is exactly what the spell is designed to do. It takes a lot more suspension of disbelief to accept something like Faerie Fire maintaining an interplanar connection, though.

And I've already stated that I'd also make an exception for a case like the OP's phase drider, for which shifting planes (at least, two particular planes) is as natural as breathing. There, it's not the Faerie Fire that's providing the interplanar connection, but the monster's own inherent phasiness.

"It takes a lot more suspension of disbelief" - I think that is where our opinions differ. This statement implies that you have decided that magic works in a specific way and you are applying constraints on how magic operates based on those ideas that are not written anywhere in the rule book.

From my perspective, I keep an open mind. I can easily imagine magic and the weave of existence pervading the multiverse touching on every plane. Magic allows portals to be opened between different planes as well as distant locations on the same plane. So it is possible to imagine that magic connects and interfaces with every part of any plane as well as every other plane (except perhaps anti-magic areas).

With this sort of idea of magic it is easy to believe that concentration can be maintained on a spell across planes because magic is pretty much everywhere. This kind of interpretation is completely consistent with the rules on what breaks concentration (planar travel is not one of them).

So, for me, imagining that concentrating on a spell can cross planes requires no suspension of disbelief whatsoever.

However, it doesn't really matter unless you are running an AL game or one where the DM has decided to play with the Rules as Written. If a DM thinks concentration should be broken by traveling to another plane then as long as they let the player's know the house rule then it doesn't matter.

P.S. Just curious - if a caster casts Banishment on a target and then decides to use Plane Shift to get their group out of there before the bad guy comes back - do you allow them to maintain concentration on Banishment? Is there any difference between concentrating on Banishment as you change planes vs any other spell?

[Tanarii]

Interesting rules hole there. They probably should have added something to concentration so it breaks when you're on a different plane, unless the spell says otherwise.

[Valmark]

Interesting rules hole there. They probably should have added something to concentration so it breaks when you're on a different plane, unless the spell says otherwise.

Unless they intended for there to not be something that forces Concentration breaks on changing planes.

If there's no hint to the intent being that plane-shifting breaks concentration (indeed the opposite, since there's at least one spell that plays on this) it's not really a hole in the rules.

[Chronos]

Quoth Keravath:

P.S. Just curious - if a caster casts Banishment on a target and then decides to use Plane Shift to get their group out of there before the bad guy comes back - do you allow them to maintain concentration on Banishment? Is there any difference between concentrating on Banishment as you change planes vs any other spell?

I can honestly say that I've never thought about it, and it wouldn't often be relevant. I'd have to think about that.

[Ionathus]

Interesting rules hole there. They probably should have added something to concentration so it breaks when you're on a different plane, unless the spell says otherwise.

I'm not too bothered by it. Anything that can cross between planes, almost by default, is going to be cooler and harder to fight than a similar thing anchored to this single, incredibly bogus plane.

Like, I can think of some incredible build or exploit for many spells of 6th level or above, but that doesn't mean they're broken -- because so very few mortals ever reach 6th-level spells, even as PCs.

[Chronos]

Sure, 6th level spells are Just That Awesome. But changing planes comes online as early as 3rd level spells, with Blink. And PCs could encounter things like portals (that they didn't make themselves) at any level.