Is target species or creature type a ‘requirement’ when duplicating a spell with Wish

dnd-5espellswish

As the question asks (above): is the creature's type one of the 'requirements' when casting a wish spell? If so, a Wish spell would have greater flexibility &/or utility.

This may have been answered (generally-partially) here in Stack Exchange (?): a Wish 'requirement' is suggested to be anything that prevents you from casting a spell. If this question is judged as a repeat question, apologies in advance. That aside, if creature-type qualifies as something that prevents the casting of a Wish spell ('case in point'), it also counts as argument-precedent and is thus useful for this answer.

Examples of using non-stress Wish when a creature's species-type is a 'requirement':

Reincarnation & Cloning of non-humanoids becomes possible via basic Wish spells (such as the reincarnation of fae (like Pixies) or the cloning of a dragon)
4th level Polymorph may be able to turn a creature into something other than a 'beast', not requiring the Wish spell to mimic the 9th level True Polymorph (True Poly is NOT 8th level or lower / would otherwise NOT work).
'Heals' may work on certain undead otherwise prohibited – or even rapid repair of Simulacra. In this example a Simulacrum specifically states they need (expensive / time consuming) repairs to be fixed and heals do not work. If one uses a Wish to cast a heal spell it could work *but only if the creature's type (Simulacrum) is considered a 'requirement'.

Do note that these are three examples only / not an extensive list.

Best Answer

If you change the spell language, it's not the spell

The standard use of wish states (PHB, 288):

The basic use of this spell is to duplicate any other spell of 8th level or lower.

Therefore by using wish to duplicate the casting of a spell of 8th level or lower, you will avoid stress.

However, if you change the spells, then you simply aren't casting that spell. You are no longer duplicating that spell, and instead you are now casting something different and special that isn't that original spell.

This means that there is stress. If you want to avoid the stress, just avoid going outside the normal wish guidelines.

Related Solutions

[RPG] How do multiple castings of True Polymorph interact

Short answer is that the spell targets the creature in its current form.

Who Is Really In There?

Regardless of the form the creature is in after the first True Polymorph, or was originally in, the creature gets a saving throw if it is unwilling to change under a given instance of this spell.

True Polymorph Targets a single Creature

True Polymorph creature-to-creature version results in a creature with a new form: another creature. Any subsequent casting is an attempt to overwrite a previous casting, but that does not change the fact that the second instance is being cast upon a creature (the new form): a creature affected by the spell gets changed into (some new form) under two conditions:

Willingly
On a failed Wisdom save.

Choose one creature or non-magical object that you can see within range. You transform the creature into a different creature, (SRD Spell Description, p. 185).

The second wizard has only one creature to changed into that owlbear, not two. If the first caster loses concentration, the dragon becomes a fighter. That is because the two don't happen at once, as you described in your example.

This is a turn based game, so something has to happen first. If the second wizard cast the spell while the first has concentration on the Polymorph, that gets adjudicated first. If the first wizard loses concentration before the second wizard casts the spell, that gets revolved (dragon becomes fighter) first.

This means that if the first wizard is still concentrating, the only creature the second wizard has to work with is the dragon.

If the second wizard casts the spell on the dragon while the other wizard is concentrating, and not after it is permanent, then resolve the conflict with the following in mind:

An unwilling creature can make a Wisdom saving throw, and if it succeeds, it isn’t affected by this spell.

1) Have the dragon make a saving throw. It is the creature being targeted. If he willingly accepts True Polymorph from the first wizard, this save should probably be rolled first: he's the creature the other wizard is trying to change into an owlbear. If he is willing to be changed, no saving throw is needed. We then address the problem of two instances of the spell trying to affect the same creature at the same time.

The target’s game statistics, including mental ability scores, are replaced by the statistics of the new form. It retains its alignment and personality.

If the dragon fails the save -- true polymorph uses the new form's stats so our changed Fighter must use the Wisdom Save for the dragon ---- then it gets turned into an owlbear ... pending the outcome of the contest between two wizards.

If the Fighter/Dragon makes the save, then no change happens.

(You could do this contest first, and if the second wizard wins, then roll the save).

Credit to @Dale M for raising this point: when two of the same spell are applied to the same target, only one affects it. (PHB p. 205)
* In the case of True Polymorph versus Polymorph, 9th level spell beats 4th level spell
* In the case of Shapechange versus True Polymorph, it is 9th level versus 9th level spell, but since the Shapechange is cast on "self" you are dealing with the save versus True Polymorph in the Shapechanged form

How do you decide between the first and second instance of the True Polymorph spell?

The first could be overcome by the second wizard's casting based on a different game rule, since there can be only one instance of that spell affecting that creature. Two characters are trying to do the same thing at once? Use rules for a Contest.

2) Who wins the Contest?(p. 58 of the Basic Rules).

Contests

Sometimes one character’s or monster’s efforts are directly opposed to another’s. This can occur when both of them are trying to do the same thing and only one can succeed ... In situations like these, the outcome is determined by a special form of ability check, called a contest. Both participants in a contest make ability checks appropriate to their efforts. They apply all appropriate bonuses and penalties, but instead of comparing the total to a DC, they compare the totals of their two checks. The participant with the higher check total wins the contest. That character or monster either succeeds at the action or prevents the other one from succeeding.

I'd recommend using the Intelligence (spell casting stat) as the basis for the contest. That means that the situation you set up about dueling concentration doesn't have a chance to happen -- it's a turn based game.

Result of the contest is either:

The first keeps his concentration up, and he wins
The second overcomes him as a result of the Contest being resolved and the dragon is changed into an owlbear.
- (Apply saving throw, or not, based on the target being willing, or not).

Do the rules specifically state that for this spell? No. What the Contest rule provides is a simple way to resolve it, keeping in mind that things happen in a sequence in a turn based game, and that only one instance of this spell can apply to a given creature at a time.

Further comments

Note the position the second wizard is in, in terms of sequence of events.

True Polymorph / Casting Time: 1 action (SRD. p. 185)

Either the second wizard succeeds in his attempt to change the dragon into something else, or he fails. You can do it by save, by contest, or both if the dragon/fighter is not willing to change into a new form.

If the fighter was not willingly changed into a dragon, he might accept the second wizard's spell and not fight it. Only an unwilling creature rolls a save versus this spell.

An unwilling creature can make a Wisdom saving throw, and if it succeeds, it isn’t affected by this spell.

How does the spell work? First, it changes a creature's shape. Then, the wizard concentrate on the creature staying in the new shape, either short term or long term. The second wizard cannot concentrate on maintaining the new shape of a creature that he did not yet change into an owlbear.

This step by step approach avoids having to rule about "who is really in there?". Even though the polymorphed creature retains its personality and alignment (who it is), you can make a ruling on whether the warrior rolls a save versus the second spell, or not. Just ask the player.

Each casting of the spell allows a save for an unwilling creature who is the target.

This interaction goes both ways: if the second wizard loses concentration, if he targeted the fighter, then the owlbear becomes a fighter. If he targeted the dragon, then the owlbear becomes a dragon.

The owlbear only changes into a dragon if the dragon was permanent. Otherwise, he becomes the Fighter, since the contest had to be decided in the second wizard's favor in order to turn the dragon into the owlbear in the first place.

[RPG] Can a 17th level sorcerer kill all demons with Simulacrum and Wish

Not necessarily, because math, and not at all in Adventurers League

AL problems:

(source)

The key problem is:

We aren't using Wish to cast Simulacrum using the "replicate a spell" feature, since that would require being in range of Xanar to cast it. Instead we use the second option to wish for the simulacrum to be made no matter how far away he is. This isn't asking for much beyond the basic, and so should be a valid wish. This does incur the 33% chance to not be able to cast Wish ever again, but that's for your simulacrums and thus doesn't matter.

Because:

No Copies of a Copy.

Simulacrums can’t cast simulacrum, or any spell that duplicates its effects.

and

You Are You; and So Is He.

If a simulacrum you have created casts wish, both you and your simulacrum suffer the stress associated with casting the spell — including the risk of being forever unable to cast wish again. The inability to cast wish extends to any simulacrum you create in the future. (p. 8)

Each of which is designed to deal with essential parts of this otherwise-legal plan.

General Problems:

tl;dr: ℵ₁ is greater than ℵ₀

Be Xanar, a 17th sorcerer. At level 17 you chose Simulacrum as your new spell known

You can't, because that's a Wizard-only spell. However, you might be able to do that with a permissive DM or with an appropriate homebrew sorcerous origin. You can also just cast it directly via wish, which you can cast multiple times if you have the right Epic Boon(s).

Next problem:

The first simulacrum uses the rod to cast Plane Shift, dropping the rod just before it leaves. The next simulacrum then takes it's turn, picking up the rod (interaction), casting Plane Shift (action), and then dropping the rod as well before it leaves (free action). In this way, the rod travels along the infinite line of simulacra, allowing all of them to cast Plane Shift.

You almost certainly can't do this. There's no time between casting and the effects happening. You could use Contingency for this (there are ways to have more spell slots around), except Plane Shift is too high of a level. Instead, you need to be friends with, or True Polymorph into, a Metallic Dragon variant spellcaster that knows Plane Shift (for reasons. You can also coerce one into service with Gate+Dominate Monster or whatever), and have your simulacra using twinned wish duplicating simulacrum. Despite the fact that this makes no sense (Wish-duplicated spells shouldn't be twinnable since you aren't casting them), it is legal via Sage Advice Compendium errata stuff:

Can my sorcerer use Twinned Spell on a spell duplicated by the casting of a wish spell? And if so, how many sorcery points does it cost? Yes, you can. It costs the number of sorcery points appropriate for the level of the spell you’re duplicating.

And so by spending 7 sorcery points your simulacra can duplicate both you and the dragon (or a simulacrum of her), or you and a simulacrum of you.

Assuming you take one extra day or use up your 8th level slot or have a relevant magic item or class feature to cast Simulacrum again without using up your 9th level slot, that also solves the need to be using the cheat-y wish instead of the normal one: since the first casting gets you two simulacra and they each still have wish ready, the first one can copy you and the second one, and the second one can copy two of those copies, and so on. One out of every 9 copies needs to be a dragon.

You could have done this with Gynosphinxes instead, but you can't simulacrum those because they can't turn into a beast or humanoid while retaining the ability to turn back like Metallic Dragons can. Since draconic spellcasting has no components, the dragon simulacra can warp parties of 8 Xanar simulacra to the Abyss without the need for rods.

Sidenote — you have infinitely many Xanar in the Material Plane for a bit here, which might be uncomfortable but doesn't have any mechanical penalties and can be dealt with by having the dragons warp sooner if it is a problem for some reason. Next problem:

Infinite simulacra of Xanar appear at every point in the Abyss, and cast an infinite number of Eldritch Blasts upon every demon there.

No, Infinite simulacra of Xanar appear at infinitely many points in the Abyss, and cast their infinite Eldritch Blasts upon infinitely many demons there. Your infinity and the Abyss are not guaranteed to be equal in size. In my games, for example, the Abyss is infinitely larger: you have only ℵ₀ simulacra while the Abyss has ℵ₀ layers with ℵ₁ squares on each layer.

Other people run the Abyss as only having ℵ₀ or some smaller number of points or spaces on each layer. In that case, this might be a larger number than the number of demons. Even so, there's no guarantee that your ℵ₀ is the same size as their ℵ₀. It might be bigger, smaller, or something else entirely — the game does not in any way define the superstructure of the Abyss. Comparing infinities is not easy, that's why ∞ - ∞ is undefined, not 0.

To solve this problem for sure, you would need a system to generate an uncountable number of simulacra. That is, you would need the demons to not be able to apply Cantor Diagonalization to your onslaught and, in so doing, show that at least one demon wasn't attacked. I am not sure if this can be done or how you would do it.

Even if you did it, your sets would each be ℵ₁ large, and you'd still have an ∞ - ∞ situation for your DM to define the result of. To get around that, you'd need to incorporate the source of the demons into your simulacrum creation, so that the number of simulacra can be shown to be greater than the number of demons at infinity and the result of the subtraction can be medium-well-defined.

You also need a mapping function to get your simulacra to not all be bunched onto the same points, but that's a smaller problem likely solved by assuming a 1-to-1 correspondence between Material Plane spaces and Abyss spaces, somewhat supported by the explanation of how planes work in the DMG.

Even then you are gonna miss infinitely many demons, though because of the next problem:

Every demon takes an infinite amount of force damage, and dies.

Not necessarily. Demons in antimagic fields won't, and, in fact, no, Xanars can't warp into such spaces! So that's infinitely many demons this won't kill.

Also, you're rolling initiative and even with infinitely many rolls you won't beat any creature who rolls higher than it is possible for you to roll or who has special abilities allowing it to go first. Any creature who goes before you might take actions to elude your army, for example by casting antimagic field or plane shift or wall of force or meld into stone or doing anything else that negates infinitely many eldritch blasts. And any creature who doesn't go before you still might escape with reactions unless they are surprised (which, admittedly, seems likely, but is still not guaranteed). And those who don't, might, like with antimagic field residents, be immune anyway for some other reason.

That said, this will still kill infinitely many demons, so it may well still be worth a try. Just watch out for the infinitely many survivors who immediately plane shift in on your position and give you a bad day.