Polymorph and the continuation of previous effects.

[Deathtongue]

1.) If a Wight gets Polymorphed into a brown bear, do they lose control of their zombies? If the polymorph gets dispelled, do they get control of their minions back?
2.) If a Wight created by Create Undead gets polymorphed into a brown bear 23 hours and 30 minutes into the casting time and the original spellcaster casts Create Undead again to assert control while they're a brown bear, does the spell work or does it fail to take effect? What if the Wight was True Polymorphed into another form of undead not covered by Create Undead, such as a Shadow?
3.) If I start as a 17th-level human Necromancer Wizard and True Polymorph my Simulacrum into a Mummy Lord, do they become a legal target for Command Undead? If not, do I still retain control of the Simulacrum? If so, would I be able to use Command Undead on the once-simulacrum and cast Simualcrum again?

[Unoriginal]

Sorry for not providing insight right now, but I have to say: your thread title sounds like the most wonderfully amazing bad Harry Potter novel parody

[Deathtongue]

I just want to point out that either interpretation, yay or nay, whether effects continue even if you're no longer a valid target/source for effects if your sheet gets replaced can lead to abuse. For example:

If True Polymorph makes it so that while the spell is in effect, a Simulacrum is no longer a Simulacrum (including the loyalty bit) a Necromancer can leash the Simulacrum by turning it into an undead and slapping it with a Command Undead. Then make another Simulacrum.
If in the above example True Polymorph doesn't change a creature's base existence, a Necromancer could use Create Undead to get them some Wights (CR3) and then True Polymorph them into something better than Wights. And then cast Create Undead every day to maintain control.


Sorry for not providing insight right now, but I have to say: your thread title sounds like the most wonderfully amazing bad Harry Potter novel parody

Funny enough, I thought of this post shortly before I read up on Rowlings on Twitter.

[JoeJ]

I just want to point out that either interpretation, yay or nay, whether effects continue even if you're no longer a valid target/source for effects if your sheet gets replaced can lead to abuse. For example:

If True Polymorph makes it so that while the spell is in effect, a Simulacrum is no longer a Simulacrum (including the loyalty bit) a Necromancer can leash the Simulacrum by turning it into an undead and slapping it with a Command Undead. Then make another Simulacrum.

So you get one undead servant of a type that you could have gained through adventuring. That's not likely to break anything.


If in the above example True Polymorph doesn't change a creature's base existence, a Necromancer could use Create Undead to get them some Wights (CR3) and then True Polymorph them into something better than Wights. And then cast Create Undead every day to maintain control.

What would you turn them into that you think would be abusive?

[Aquillion]

I feel like this has to be decided on a case-by-case basis.


1.) If a Wight gets Polymorphed into a brown bear, do they lose control of their zombies? If the polymorph gets dispelled, do they get control of their minions back?
Going by strict mechanics, I would say they retain control. The DM could conclude that the zombies no longer recognize the weight and that the wight no longer has the intellect to do anything with this control, though (and I suspect almost all of them would go for that.) So for practical purposes their control would cease to matter while they were a bear.

If the Polymorph was dispelled, they could resume controlling their zombies.


2.) If a Wight created by Create Undead gets polymorphed into a brown bear 23 hours and 30 minutes into the casting time and the original spellcaster casts Create Undead again to assert control while they're a brown bear, does the spell work or does it fail to take effect? What if the Wight was True Polymorphed into another form of undead not covered by Create Undead, such as a Shadow?
I was going to say it fails, but by a strict reading of that use of Create Undead, I think the RAW is that it succeeds:


The creature is under your control for 24 hours, after which it stops obeying any Command you have given it. To maintain control of the creature for another 24 hours, you must cast this spell on the creature before the current 24-hour period ends. This use of the spell reasserts your control over up to three creatures you have animated with this spell, rather than animating new ones.

It just says "the creature", nothing about them having to be undead. It's still the same creature, just in a different form, so it would technically work. My assumption would be that most DMs would say it doesn't, though, since the intent is clearly that Create Undead asserts control via some aspect of their undead nature. But even in terms of in-setting metaphysics, it's ambiguous enough that it could go either way.


3.) If I start as a 17th-level human Necromancer Wizard and True Polymorph my Simulacrum into a Mummy Lord, do they become a legal target for Command Undead?Yes. This one is easy. True Polymorph makes them undead - I can't see any argument (whether RAW, RAI, metaphysics, or balance-wise) to treat this any other way.

Why would you need to, though? True Polymorph doesn't change their mental state, so it's still friendly to you. Some DMs might rule that it no longer must obey you, but I can't see why it would suddenly become unfriendly.


If so, would I be able to use Command Undead on the once-simulacrum and cast Simualcrum again?You can, but at least going by RAW, I'd say the original will still be destroyed - it's still the same creature, just in a different form. Again, some DMs may choose to treat it differently based on their interpretation of setting metaphysics.


So you get one undead servant of a type that you could have gained through adventuring. That's not likely to break anything.Well, being able to produce them at-will is a bit stronger than just finding one. Mummy Lords don't grow on trees. But Simulacrum isn't cheap if you're casting it normally, and casting it via Wish is already more exploitive than anything OP is trying to pull off here.


If True Polymorph makes it so that while the spell is in effect, a Simulacrum is no longer a Simulacrum (including the loyalty bit) a Necromancer can leash the Simulacrum by turning it into an undead and slapping it with a Command Undead. Then make another Simulacrum.
If in the above example True Polymorph doesn't change a creature's base existence, a Necromancer could use Create Undead to get them some Wights (CR3) and then True Polymorph them into something better than Wights. And then cast Create Undead every day to maintain control.Even if you remove the loyalty bit, though... True Polymorph doesn't overwrite their brain. I don't see any reason why a True Polymorphed simulacrum would immediately turn on you.

I think it might eventually deviate from its programming, mentally, over time, as it realizes it can now behave however it pleases. But it's not like turning it into a Mummy Lord will suddenly give it generic Mummy Lord hostility, since True Polymorph from one creature to another doesn't change the creature mentally aside from what's implied by raising or lowering its mental stats.

[Rukelnikov]

I just want to point out that either interpretation, yay or nay, whether effects continue even if you're no longer a valid target/source for effects if your sheet gets replaced can lead to abuse. For example:

If True Polymorph makes it so that while the spell is in effect, a Simulacrum is no longer a Simulacrum (including the loyalty bit) a Necromancer can leash the Simulacrum by turning it into an undead and slapping it with a Command Undead. Then make another Simulacrum.
If in the above example True Polymorph doesn't change a creature's base existence, a Necromancer could use Create Undead to get them some Wights (CR3) and then True Polymorph them into something better than Wights. And then cast Create Undead every day to maintain control.



Funny enough, I thought of this post shortly before I read up on Rowlings on Twitter.

Strangely enough you choose two of the most abusable spells in the game, but use them for less abusive things :P.

Simulacrum can be completely broken by creating an army of you.(which you can subsequently True Polymorph into whatever you want)

True Polymorph can turn rocks into an army of T-Rexes.

[Aquillion]

True Polymorph can turn rocks into an army of T-Rexes.
Sort of. The spell says that if it becomes permanent, "you no longer control the creature. It might remain friendly to you, depending on how you have treated it."

So you, at best, have a bunch of friendly T-Rexes, but they're not necessarily your personal army or something.

[Rukelnikov]

Sort of. The spell says that if it becomes permanent, "you no longer control the creature. It might remain friendly to you, depending on how you have treated it."

So you, at best, have a bunch of friendly T-Rexes, but they're not necessarily your personal army or something.

Yeah, that's true, an army of T-Rexes as pets is still pretty cool though.

[JackPhoenix]

Yeah, that's true, an army of T-Rexes as pets is still pretty cool though.

At least until you realize that while the dinosaurs may be friendly to *you*, the same isn't true about the other party members. Or even other T-Rexes.

[Potato_Priest]

If in the above example True Polymorph doesn't change a creature's base existence, a Necromancer could use Create Undead to get them some Wights (CR3) and then True Polymorph them into something better than Wights. And then cast Create Undead every day to maintain control.


I guess you could use this to get some CR3 allies of your choice from the monster manual, but how oeverpowered is that really? You still can't go above CR3 due to the restrictions of true polymorph, so it seems like a reasonable level of power and flexibility for a caster to gain from a 9th level spell.

[Rukelnikov]

At least until you realize that while the dinosaurs may be friendly to *you*, the same isn't true about the other party members. Or even other T-Rexes.

True, maybe prodigy for expertise in Animal Handling could come useful.

[JackPhoenix]

I guess you could use this to get some CR3 allies of your choice from the monster manual, but how oeverpowered is that really? You still can't go above CR3 due to the restrictions of true polymorph, so it seems like a reasonable level of power and flexibility for a caster to gain from a 9th level spell.

Step 1: turn the creature into object, wait until the change is permanent
Step 2: turn the object into a creature of CR up to 9.

[JoeJ]

Step 1: turn the creature into object, wait until the change is permanent
Step 2: turn the object into a creature of CR up to 9.

Or you could eliminate step 1 and just turn boulders into creatures. That would let you do it in 1 day instead of 2.

[MaxWilson]

Or you could eliminate step 1 and just turn boulders into creatures. That would let you do it in 1 day instead of 2.

I believe the intent here is to control e.g. eight CR 9 Abominable Yetis with one casting per day of Animate Dead, by turning skeletons into rocks into Abominable Yetis.

[Rukelnikov]

Step 1: turn the creature into object, wait until the change is permanent
Step 2: turn the object into a creature of CR up to 9.

I'm not sure this works. True Polymorph is permanent, not instantaneous, magic is still at work, the effect is still on you. I think you can't have 2 instances of the same "feature"(?) affecting you at the same time, thus attempting to TP the rocks into a creature would cancel the first casting of TP and thus render the wights invalid targets for Object to Creature.

[JoeJ]

I believe the intent here is to control e.g. eight CR 9 Abominable Yetis with one casting per day of Animate Dead, by turning skeletons into rocks into Abominable Yetis.

I don't think that works. Either the control would be lost as soon as they become objects, or else they would still be creatures even in rock form (because True Polymorph doesn't have a duration of instantaneous) and the CR limit would still apply.

[MaxWilson]

I don't think that works. Either the control would be lost as soon as they become objects, or else they would still be creatures even in rock form (because True Polymorph doesn't have a duration of instantaneous) and the CR limit would still apply.

Perhaps. That's Deathtongue's point though, or at least part of it--either interpretation is potentially exploitable. E.g. if effects do persist while Polymorphed, then instead of using Create Undead VI to control three ghouls (probably not worth it) you can use it to control three Bronze Scouts (possibly worth it due to weapon immunity). Or you could Planar Bind an upcast Elemental and then transform it into a Shield Guardian.

Another variation on this theme is "If effects don't persist across Polymorph, what happens if you True Polymorph the Tarrasque into a Gloomweaver and then Magic Jar into that Gloomweaver before ending True Polymorph?" Whose soul is now in the Tarrasque's Body?

[JackPhoenix]

I don't think that works. Either the control would be lost as soon as they become objects, or else they would still be creatures even in rock form (because True Polymorph doesn't have a duration of instantaneous) and the CR limit would still apply.

Look a bit higher up in the chain. It all assumes the "creature's base existence" allows the control to be retained, which is not covered by the RAW, one way or the other. Creature turned into an object is an object, and objects don't have CR.

[Rukelnikov]

Look a bit higher up in the chain. It all assumes the "creature's base existence" allows the control to be retained, which is not covered by the RAW, one way or the other. Creature turned into an object is an object, and objects don't have CR.

Creature turned into an object is an object, but the second casting of TP makes it no longer a valid target for Object to Creature.

[JoeJ]

Look a bit higher up in the chain. It all assumes the "creature's base existence" allows the control to be retained, which is not covered by the RAW, one way or the other. Creature turned into an object is an object, and objects don't have CR.

I'm disagreeing with that. If it's an object, it's not affected by spells that don't affect objects, including the control. If it retains creature status you can retain control, but then you can't use True Polymorph to turn it into something with a higher CR than it had originally.

The plan only works if you say that the target is a both creature and an object, counting as whichever is most convenient at the moment.

[MaxWilson]

I'm disagreeing with that. If it's an object, it's not affected by spells that don't affect objects, including the control. If it retains creature status you can retain control, but then you can't use True Polymorph to turn it into something with a higher CR than it had originally.

The plan only works if you say that the target is a both creature and an object, counting as whichever is most convenient at the moment.

Let me make sure I understand you. Given the following sequence of events, which steps would you say are infeasible/illegal?

(1) Wizard casts Animate Dead on some corpses, makes four zombies.
(2) Other wizards cast True Polymorph on the zombies, turning them into Hadrosaurs (size large). An hour later, the transformation into hadrosaurs is permanent (until dispelled).
(3) Other wizards cast True Polymorph on the hadrosaurs, turning them into large rocks. An hour later, the transformation into rocks is permanent (until dispelled).
(4) Other wizards cast True Polymorph on the rocks, turning them into Abominable Yetis. An hour later, the transformation into Abominable Yetis is permanent (until dispelled).
(5) Twenty-one hours later, the original wizard recasts Animate Dead on the original creatures produced by the spell, who are now Abominable Yetis.

Related question: in the following sequence of events, would you say the bard's spell has the intended effect?

(1) Mind Flayer casts Dominate Person on a low-Wisdom barbarian. The barbarian is dominated.
(2) Bard casts Polymorph on the barbarian, turning them into a chicken. A chicken is not a person, so (the bard reasons) Dominate Person ends. The barbarian is now a non-dominated chicken.
(3) Bard immediately ceases concentration on Polymorph. The barbarian is now neither dominated nor a chicken.

Note that the bard's theory of how Polymorph works is the exact opposite of the wizard's theory. One of them must be correct, although the wizard's theory of Polymorph and ongoing effects could be correct but his plan could still fail at step #4 because of a failure in his theory of True Polymorphing objects ("can't True Polymorph those rocks into Abominable Yetis because CR 1/4 is less than CR 9"). In this case the most powerful exploit is not "control CR 9 creatures with Animate Dead" but only "control arbitrary CR 9 creatures via Planar Binding even if they aren't currently elementals" or perhaps "Magic Jar into any creature's body even if it was only briefly humanoid."

[PhoenixPhyre]

Effects with the same name don't stack. True polymorph is an ongoing effect, since even the "permanent" version can be dispelled. Thus, it cannot be chained--casting it again on the same target (even if the effect was "permanent") uses the original stat block as a starting point.

So if you TP a zombie into an object and then try to TP that object into something, the first casting is dispelled and so the only legal new forms are those for a zombie, not an object.

[MaxWilson]

Effects with the same name don't stack. True polymorph is an ongoing effect, since even the "permanent" version can be dispelled. Thus, it cannot be chained--casting it again on the same target (even if the effect was "permanent") uses the original stat block as a starting point.

So if you TP a zombie into an object and then try to TP that object into something, the first casting is dispelled and so the only legal new forms are those for a zombie, not an object.

In this is the case there are a bunch of fun exploits that have already been mentioned in this thread, e.g. Planar Binding CR 7 elementals and then True Polymorphing them into Shield Guardians.

[JoeJ]

Let me make sure I understand you. Given the following sequence of events, which steps would you say are infeasible/illegal?

(1) Wizard casts Animate Dead on some corpses, makes four zombies.
(2) Other wizards cast True Polymorph on the zombies, turning them into Hadrosaurs (size large). An hour later, the transformation into hadrosaurs is permanent (until dispelled).
(3) Other wizards cast True Polymorph on the hadrosaurs, turning them into large rocks. An hour later, the transformation into rocks is permanent (until dispelled).
(4) Other wizards cast True Polymorph on the rocks, turning them into Abominable Yetis. An hour later, the transformation into Abominable Yetis is permanent (until dispelled).
(5) Twenty-one hours later, the original wizard recasts Animate Dead on the original creatures produced by the spell, who are now Abominable Yetis.

Steps 3, 4, and 5.


Related question: in the following sequence of events, would you say the bard's spell has the intended effect?

(1) Mind Flayer casts Dominate Person on a low-Wisdom barbarian. The barbarian is dominated.
(2) Bard casts Polymorph on the barbarian, turning them into a chicken. A chicken is not a person, so (the bard reasons) Dominate Person ends. The barbarian is now a non-dominated chicken.
(3) Bard immediately ceases concentration on Polymorph. The barbarian is now neither dominated nor a chicken.

That I don't have a problem with, although I would not allow the dominated barbarian to voluntarily fail their save against the Polymorph. Balance-wise, you're using a 4th level spell to do what you could have done with a 3rd level Dispel Magic, which is not going to break anything.

[MaxWilson]

Steps 3, 4, and 5.

Step 3, really? You can't turn the hadrosaurs into rocks? Why ever not? Would that mean I can protect myself against Dominate Person just by casting Dominate Person on myself first?

[JoeJ]

Step 3, really? You can't turn the hadrosaurs into rocks? Why ever not? Would that mean I can protect myself against Dominate Person just by casting Dominate Person on myself first?

As others have pointed out, the effects of the same spell cast multiple times don't stack. Now if you want to stop concentrating on the 1st TP while the 2nd one is still in effect so that they're no longer overlapping, then you could do it. But in that case, what was the point of the 1st one?

Sure. If you want to spend a 5th level slot and concentration on dominating yourself, go for it. The 2nd Dominate Person won't affect you until the 1st one expires. That would be a pretty clever defense, although far less than optimal in many cases.

[PhoenixPhyre]

In this is the case there are a bunch of fun exploits that have already been mentioned in this thread, e.g. Planar Binding CR 7 elementals and then True Polymorphing them into Shield Guardians.

That doesn't work like you want (the Shield Guardian is loyal to a bracelet, which you don't get with true polymorph), and I fail to see how using a 9th level spell for something so trivial is an exploit anyway.

[MaxWilson]

As others have pointed out, the effects of the same spell cast multiple times don't stack. Now if you want to stop concentrating on the 1st TP while the 2nd one is still in effect so that they're no longer overlapping, then you could do it. But in that case, what was the point of the 1st one?

Sure. If you want to spend a 5th level slot and concentration on dominating yourself, go for it. The 2nd Dominate Person won't affect you until the 1st one expires. That would be a pretty clever defense, although far less than optimal in many cases.

The effects of multiple spells don't stack, but in case of conflict, the most powerful or most recent one is supposed to take effect. That's why I'm so surprised to hear you say that the hadrosaurs wouldn't become rocks.


That doesn't work like you want (the Shield Guardian is loyal to a bracelet, which you don't get with true polymorph), and I fail to see how using a 9th level spell for something so trivial is an exploit anyway.

The bracelet is irrelevant. The Shield Guardian in this scenario is subject to Planar Binding, not a bracelet. It could equally well be a mind flayer or a silver dragon.

Remember that we're talking about the scenario where Polymorph doesn't end existing spells (option A), not option B where it does.

[NaughtyTiger]

Effects with the same name don't stack. True polymorph is an ongoing effect, since even the "permanent" version can be dispelled. Thus, it cannot be chained--casting it again on the same target (even if the effect was "permanent") uses the original stat block as a starting point.

So if you TP a zombie into an object and then try to TP that object into something, the first casting is dispelled and so the only legal new forms are those for a zombie, not an object.

I agree that they do not chain. But disagree with the "original stat block" is the starting point

Consider Polymorph (not True Polymorph)
Bard polymorphs ally (wisdom save +8) into a T-Rex (wisdom save +1).
Enemy wizard polymorphs unwilling T-Rex into duck.

Which wisdom save does the T-Rex use?

I contend it is a T-Rex, so +1.
But if it "uses the original stat block as a starting point" then it would be +8.


When does the Bard's spell end?

I contend it as after the T-Rex fails the save and is changed.
But if "the first casting is dispelled" then the Bard's spell ends when the wizard casts it, before the non-T-rex ally rolls the +8 save.


Alternately consider,
Bard polymorphs ally (wisdom save +8) into a T-Rex (wisdom save +1).
Enemy casts Animal Friendship.

Does the ally even have to roll?

I contend it is a beast, so yes.
But if it "uses the original stat block as a starting point" then the ally is not a beast, and the spell fails.



The effects of multiple spells don't stack, but in case of conflict, the most powerful or most recent one is supposed to take effect. .
Duh, this is a much shorter way of expressing my view.

[PhoenixPhyre]

I agree that they do not chain. But disagree with the "original stat block" is the starting point
Consider Polymorph (not True Polymorph)

Bard polymorphs ally (wisdom save +8) into a T-Rex (wisdom save +1).
Enemy wizard polymorphs unwilling T-Rex into duck.

Which wisdom save does the T-Rex use?

I contend it is a T-Rex, so +1.
But if "uses the original stat block as a starting point" then it would be +8.



When does the Bard's spell end?

I contend it as after the T-Rex fails the save and is changed.
But if "the first casting is dispelled" then the Bard's spell ends when the wizard casts it, before the non-T-rex ally rolls the +8 save.


You misunderstand. The base stat block controls here because spells don't stack with themselves. Trying to true polymorph an already true polymorphed creature either fails outright or cancels the previous spell. Otherwise you'd have an illegal situation--a creature transformed into something with greater CR than itself. And that's not possible by true polymorph. You could, however, take a true polymorphed creature and polymorph it (the 4th level spell) into something else. That's fine, and when the polymorph ends, the true polymorph shape would come back. And if you did so, the creature would use it's TP-granted save modifiers, rather than its base ones.

So with the "chaining" case, the order of operations looks like
1) initial TP goes permanent.
2) Second TP is cast. One of two things happens, at DM's discretion.
2a) The second cast fails outright, as it's a weaker effect (shorter duration) than the existing effect.
2b) The second cast replaces the first one.
3) If 2a didn't happen, then the second cast must check the creature's CR. But the first cast is already gone and can't come back, so there's no modified CR to check. The base CR controls.

I'd say (both as a player and as a DM) that step 2a is what's supposed to happen if the casters of both TP are the same. For dueling spells, I'd go with whichever combined spell-casting modifier is higher, defaulting to "second one fails" in a tie.

[Rukelnikov]

I agree that they do not chain. But disagree with the "original stat block" is the starting point

Consider Polymorph (not True Polymorph)
Bard polymorphs ally (wisdom save +8) into a T-Rex (wisdom save +1).
Enemy wizard polymorphs unwilling T-Rex into duck.

Which wisdom save does the T-Rex use?

I contend it is a T-Rex, so +1.
But if it "uses the original stat block as a starting point" then it would be +8.


When does the Bard's spell end?

I contend it as after the T-Rex fails the save and is changed.
But if "the first casting is dispelled" then the Bard's spell ends when the wizard casts it, before the non-T-rex ally rolls the +8 save.


Alternately consider,
Bard polymorphs ally (wisdom save +8) into a T-Rex (wisdom save +1).
Enemy casts Animal Friendship.

Does the ally even have to roll?

I contend it is a beast, so yes.
But if it "uses the original stat block as a starting point" then the ally is not a beast, and the spell fails.


It uses the +1.

However the "original stat black" thing is the following, assume the enemy Gruul Wizard casted Dominate Beast instead of another Polymorph, and it went thru, now AllyDino is dominated, if Bard stops concentrating in Polymorph, the Dominate carries on, but since Ally is no longer a valid target for Dominate Beast, the spell automatically ends.

[JoeJ]

The effects of multiple spells don't stack, but in case of conflict, the most powerful or most recent one is supposed to take effect. That's why I'm so surprised to hear you say that the hadrosaurs wouldn't become rocks.

More powerful, yes. Where do you see that the most recent takes priority for equally powerful effects?

[PhoenixPhyre]

The bracelet is irrelevant. The Shield Guardian in this scenario is subject to Planar Binding, not a bracelet. It could equally well be a mind flayer or a silver dragon.

Remember that we're talking about the scenario where Polymorph doesn't end existing spells (option A), not option B where it does.

So you spent 2 high level slots to gain temporary (24 hours) command of something less powerful than the thing you already bound. So?

All of the interesting features of the shield guardian are tied to the wearer of the bracelet, not the creator or it being obedient. Only regeneration isn't. And without those interesting features, it's a low-damage, moderately tanky creature. Same HP (or worse), fewer immunities, way less damage.

[MaxWilson]

More powerful, yes. Where do you see that the most recent takes priority for equally powerful effects?

PHB, pg 205, "Combining Magical Effects". See errata: https://media.wizards.com/2018/dnd/downloads/PH-Errata.pdf

[New] Combining Magical Effects
(p. 205). In the first paragraph, the
following sentence has been added to
the first paragraph: “Or the most recent
effect applies if the castings are equally
potent and their durations overlap.”



So you spent 2 high level slots to gain temporary (24 hours) command of something less powerful than the thing you already bound. So?

24 hours? Are we even talking about the same scenario? Try "one year."

And "same or lower CR" is not the same thing as "less powerful" anyway. You can gain access to different, often better abilities. For example, turning CR 5 water elementals into CR 4 Couatls is almost certainly an upgrade--certainly in terms of spellcasting it is, and there's also the weapon immunities, AC, poison, and constricting attacks to consider.

[PhoenixPhyre]

PHB, pg 205, "Combining Magical Effects". See errata: https://media.wizards.com/2018/dnd/downloads/PH-Errata.pdf

[New] Combining Magical Effects
(p. 205). In the first paragraph, the
following sentence has been added to
the first paragraph: “Or the most recent
effect applies if the castings are equally
potent and their durations overlap.”


But the second true polymorph isn't as potent. Its duration is quite a bit shorter. So it fails outright.

Even if you decide that the second one replaces the first, you're still stuck with checking the base creature's CR, because otherwise the spells would have stacked, even for an instant (which they can't). By the time the second one checks the conditions, the first spell has to be completely gone. So no chain for you.

[NaughtyTiger]

You misunderstand.

One of us misunderstood.
I asked about Polymorph, and you talked about True Polymorph exclusively.

[JoeJ]

PHB, pg 205, "Combining Magical Effects". See errata: https://media.wizards.com/2018/dnd/downloads/PH-Errata.pdf

[New] Combining Magical Effects
(p. 205). In the first paragraph, the
following sentence has been added to
the first paragraph: “Or the most recent
effect applies if the castings are equally
potent and their durations overlap.”


Okay, so you can turn the zombies, that were temporarily hadrosaurs, into rocks. That still doesn't give you anything above their CR. And it makes dominating yourself useless for the purpose of resisting being dominated by someone else.

[MaxWilson]

Okay, so you can turn the zombies, that were temporarily hadrosaurs, into rocks. That still doesn't give you anything above their CR. And it makes dominating yourself useless for the purpose of resisting being dominated by someone else.

Right, that's why I was surprised to hear you suggest it.

Even if you can't turn hadrosaurs into rocks, you can still turn Planar Bound elementals into couatls, ghasts into intellect devourers, mummies into Green Hags (which can coven up for spellcasting), etc. If this works at a given table there are lots of clear applications--once you get 9th level spells, which you probably never will.

Prior to that the best-possible combo is probably Polymorph + Dominate Beast, at 4th level.

[NaughtyTiger]

But the second true polymorph isn't as potent. Its duration is quite a bit shorter.

Bard uses Polymorph on Ally turning him into T-Rex, and is concentrating for 17 minutes.
Enemy uses Polymorph on T-Rex...

Based on your definition of duration:
The Bard does not automatically lose concentration.
The Ally remains a T-Rex until the Bard stops concentrating or ally is a T-rex for 1 hour.
The Enemy cannot use Polymorph on T-Rex cuz the Enemy cannot guarantee that his duration of Polymorph would last longer than 17-minutes.

[PhoenixPhyre]

One of us misunderstood.
I asked about Polymorph, and you talked about True Polymorph exclusively.

Because that was the entire point of this thread. Your polymorph example was a response to a whole thread talking about "permanent" true polymorph.


Bard uses Polymorph on Ally turning him into T-Rex, and is concentrating for 17 minutes.
Enemy uses Polymorph on T-Rex...

Based on your definition of duration:
The Bard does not automatically lose concentration.
The Ally remains a T-Rex until the Bard stops concentrating or ally is a T-rex for 1 hour.
The Enemy cannot use Polymorph on T-Rex cuz the Enemy cannot guarantee that his duration of Polymorph would last longer than 17-minutes.

You can't reason from polymorph to true polymorph. Spells are individual things, each their own package of exceptions. In an exception-based game, you cannot generate general rules from looking at specific rules. That's a reasoning error. And polymorph isn't in play in the scenario under discussion. You can't change the example when convenient and expect that the same reasoning still applies.

The duration of a spell is what is listed in the spell block (in this case "concentration, up to X"), not the remaining duration (otherwise the "if the durations overlap" phrase would be meaningless). Thus, the durations overlap and either the stronger one takes precedence or the later one takes control (if they're the same strength, however you wish to define that).

True polymorph has a line that changes the duration (from "concentration, up to X" to "until dispelled"). Since "until dispelled" is indefinite, while "concentration, up to X" is not, the durations do not overlap and the second spell fails. Or not. It's up to the DM to rule exactly how that applies. But in neither case can you get stacking.

[MaxWilson]

True polymorph has a line that changes the duration (from "concentration, up to X" to "until dispelled"). Since "until dispelled" is indefinite, while "concentration, up to X" is not, the durations do not overlap and the second spell fails. Or not. It's up to the DM to rule exactly how that applies. But in neither case can you get stacking.

What do you mean, they don't overlap? Are you interpreting the word "overlap" in an unusual way?

[PhoenixPhyre]

What do you mean, they don't overlap? Are you interpreting the word "overlap" in an unusual way?

As in--the second one will finish before the first ends. More specifically, the operative clause here is the "of equal power" one. Which, to me, having unequal durations fails. Just like trying to replace an upcast hex with a 1st-level hex. Same effect, different power.

Having said that, I am open to either one of my 2a (second spell just fails) or 2b (second one takes priority as more recently cast but same power, but does not chain). I'd rule 2a in the case of true polymorph for simplicity, but wouldn't complain about 2b, and if someone had a strong feeling in that direction, I'd go with that. Because you really can't do anything broken with it...at least anything more broken than a 9th level spell already is.

[MaxWilson]

As in--the second one will finish before the first ends.

That's not what overlap means. Overlap: "extend over so as to cover partly."

If my shift today overlaps with your shift, that doesn't mean I stay until you go home. It just means there's at least part of the time when we're both here.


More specifically, the operative clause here is the "of equal power" one.

Right, I got that part of your interpretation before (though I disagree with it--the rules text in question clearly distinguishes effect strength from duration, so you can't use longer duration as evidence of stronger effect), but what really grabbed my attention was the part where you said the durations don't overlap because one of them isn't permanent.

Oh well. I disagree.

[NaughtyTiger]

Because that was the entire point of this thread. Your polymorph example was a response to a whole thread talking about "permanent" true polymorph.

You can't reason from polymorph to true polymorph.

You are "reasoning" a lot into True Polymorph that isn't there.

True polymorph doesn't say additional castings are applied to the "original stat block".
You are basing that on a general rule.
That interpretation of general rule doesn't hold up with other spells.
Therefore, your interpretation is inconsistent.

[PhoenixPhyre]

You are "reasoning" a lot into True Polymorph that isn't there.

True polymorph doesn't say additional castings are applied to the "original stat block".
You are basing that on a general rule.
That general rule doesn't hold up with other spells.
Therefore, your interpretation is incorrect.

No, the other spells implicate different things differently.

Let's go through this again.

If you could chain true polymorph (the only contention I'm willing to stand absolutely firm on, the others could go either way), then the two castings would have to coexist for even an infinitesimal duration. But the stacking rules say they can't--either the second fails or the second replaces the first.

We know that the original stat block information is still there even if the spell is permanent--otherwise the creature couldn't revert when the spell ends. So true polymorph (even permanent) does not overwrite this information, it merely hides it.

And the conditions for a spell must be true continuously, otherwise it ends. So by the time the 2nd true polymorph checks the "is target an object" condition (for the CR to be valid), the first TP is already gone. So there's nothing there other than the original stat block (which must still exist) to read.

[PhoenixPhyre]

That's not what overlap means. Overlap: "extend over so as to cover partly."

If my shift today overlaps with your shift, that doesn't mean I stay until you go home. It just means there's at least part of the time when we're both here.



Right, I got that part of your interpretation before (though I disagree with it--the rules text in question clearly distinguishes effect strength from duration, so you can't use longer duration as evidence of stronger effect), but what really grabbed my attention was the part where you said the durations don't overlap because one of them isn't permanent.

Oh well. I disagree.

I'll admit. That part (the overlapping thing) could probably have been phrased better in a different way. But the point about not stacking (which is the only part I really care about) still stands. Either way, you can't chain true polymorph.

[NaughtyTiger]

No, the other spells implicate different things differently.

Let's go through this again.

If you could chain true polymorph (the only contention I'm willing to stand absolutely firm on, the others could go either way), then the two castings would have to coexist for even an infinitesimal duration. But the stacking rules say they can't--either the second fails or the second replaces the first.

We know that the original stat block information is still there even if the spell is permanent--otherwise the creature couldn't revert when the spell ends. So true polymorph (even permanent) does not overwrite this information, it merely hides it.

And the conditions for a spell must be true continuously, otherwise it ends. So by the time the 2nd true polymorph checks the "is target an object" condition (for the CR to be valid), the first TP is already gone. So there's nothing there other than the original stat block (which must still exist) to read.

Ah, you are treating the 2nd casting as an uncontested Dispel Magic + new casting of True Polymorph. I guess I am okay with the interpretation that you get a free 9th level Dispel Magic with each casting.

[JoeJ]

Right, that's why I was surprised to hear you suggest it.

The part you quoted isn't in the errata I looked at. There must have been some changes since I printed my copy.

[MaxWilson]

The part you quoted isn't in the errata I looked at. There must have been some changes since I printed my copy.

Yes, these ones are new to the 10th printing. Source: https://media.wizards.com/2018/dnd/downloads/PH-Errata.pdf

It's the same iteration of errata that made monks good grapplers, by changing the rules for grappling incapacitated creatures, and also fixed Contagion.

[NaughtyTiger]

But the second true polymorph isn't as potent. Its duration is quite a bit shorter.

I do have a problem with potent including duration.
Potent is the strength of the effect
Duration is the length of the effect