Increasing number of any-school spells for an Arcane Trickster by a strict RAW reading?

Question

A single-class Arcane trickster typically gains spells in the schools of Illusion and Enchantment.

They are permitted a single "any-school" spell at 3rd level (upon choosing the Arcane Trickster archetype) and again at 8th level, such that by 8th level they may know two spells that are not from Illusion or Enchantment.

You know three 1st-level wizard spells of your choice, two of which you must choose from the enchantment and illusion spells on the wizard spell list. (PHB)

The spells you learn at 8th, 14th, and 20th level can come from any school of magic. (PHB)

They are also permitted to replace spells when they level, and while this typically changes the spell identity, it does not change the number of "any-school" spells that they know.

Whenever you gain a level in this class, you can replace one of the wizard spells you know with another spell of your choice from the wizard spell list. The new spell must be of a level for which you have spell slots, and it must be an enchantment or illusion spell, unless you’re replacing the spell you gained at 3rd, 8th, 14th, or 20th level from any school of magic. (PHB as modified by 2020 errata (emphasis mine) and see this question)

However, suppose an Arcane Trickster wanted access to more any-school spells and did not mind limiting their access to Illusion and Enchantment spells in order to do so.

Would the following work?

Upon becoming an Arcane Trickster at 3rd level (3 spells known), they make sure that their third, "any school of magic" spell is actually from either the illusion or enchantment school, and a spell they are not interested in using beyond being a placeholder. Say, for example, Illusory Script.

At 4th level (4 spells known) they gain an illusion or enchantment (IE) spell, but they also replace Illusory Script with the first non-illusion, non-enchantment (NINE) spell they want. They can do this because 'it must be an enchantment or illusion spell, unless you’re replacing the spell you gained at 3rd, 8th, 14th, or 20th level from any school of magic,' and it is the spell they gained at 3rd level from any school of magic.

At 5th level (4 spells known) they do not gain a new spell, but they can replace one of their original two (IE) spells with Illusionary Script. They can do this because the replacement is an IE spell.

At 6th level (4 spells known) they do not gain a new spell, but they can replace Illusionary Script with a second NINE spell. They can do this because while that instance of the spell was not gained at third level, it is certainly "the spell they gained at 3rd level from any school of magic," that is, the same spell identity. [And this definition is what the strategy depends on] We can see that rather than waiting until 8th level for a second NINE spell, this way they can get one at 6th.

At 7th level (5 spells known) they gain a new spell, and take Illusionary Script again. They can also replace a spell, and likely switch out the first level IE spell they learned with a second level one, since they now have access to second level spell slots.

At 8th level (6 spells known) they gain a new spell of any school, and take a second-level NINE spell (their third NINE spell). They can also replace a spell, and replace Illusionary Script again with a another second-level NINE spell (their fourth NINE spell).

Thus by 8th level, rather than having only two non-illusion, non-enchantment spells, they have four, which is two-thirds of their known spells.

This seems to me to be permissible under RAW. Am I wrong in my reading?

Note that currently I am the DM in the game in which there is already an 11th level artificer; I am not asking with the intent of using this as a player, and answers of 'ask your DM if they would allow this' are not necessary. Rather, my greatest contact with the 5e community comes through this site. My question is about whether my understanding of what the rules actually say is correct, and if so, whether people actually play this way ('that's what the rules say, duh') or not ('sure, that's what the rules say, but we all know what they actually mean').

If an answer posits that the rules do not intend to permit this exploit, a good answer would explain on what basis they draw the conclusion that RAW are not RAI. A great answer would suggest a rewrite of the feature in language that unambiguously expresses its intent.

Answer 1

RAW is up for interpretation, but your reading is so very obviously not intended.

You have provided the so very obviously unintended reading of the rules as written. The question here is the meaning of:

the spell they gained at 3rd level from any school of magic

You are claiming that “illusory script” is always and forever the answer to that question. And in some sense you would be right. But for the purposes of learning spells at 6th level, it seems to me to be a perfectly reasonable interpretation of the rules as written to say “illusory script is the spell I learned at 5th level, so it does not qualify to be replaced with a NINE spell.”

Even if we are saying “I will adhere to strict rules as written”, I would argue this one is going to be up to the DM, and the reading you provide is so obviously not the intended reading of the feature. It seems quite obvious that the intent is that an Arcane Trickster knows at most four NINE spells by 20th level.

Answer 2

It works partially.

You are the DM who argues that this works, so there is little conflict in that regard. Make sure that your table is on the same page as you, and don't be surprised if, in an AL situation, a different DM would contest your ruling even if it is strictly correct but works only partially when considering:

Whenever you gain a level in this class, you can replace one of the wizard spells you know with another spell of your choice from the wizard spell list.

The order of logic makes it possible to use the exploit every other level (that meets requirements) since you have to already "know" the spell that you replace when (so before) you gain a level - which you have to select again every time before you can replace it. You can't circumvent this state because "known" is a binary condition, so either you do know a spell, or you don't.

You didn't tag this question as AL, so you are also good in that regard. You are the DM at your table, and to give your player these options, you don't have to exploit semantic loopholes - you can offer options to your player in the purview of your DM role as long as everyone is on the same page.

Answer 3

This reading and application of the rules relies on a lot of things.

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What do the words mean?

Primarily, it requires that the other people at your table, one of whom MUST be the DM, accept and agree to your interpretation of "the spell you chose at 3rd level" as applying to the abstract version on the wizard spell list that you choose from (which allows 'you picked it at 3rd level' to survive retraining), and not the instance of it on your spell list (which does not). I'll be calling these "the former interpretation" and "the latter interpretation" respectively.

In all the time I've been playing 5E, I have not met anyone who read the rule and did not immediately come to the latter interpretation, much less even conceived the former interpretation without having it explicitly explained to them, much less adopted it over the latter interpretation. And for all I know (explained below), that could very well include you.

Now it seems like part of the question is asking 'but what do the words themselves actually mean?', asking for a platonic, objective proof of meaning one way or the other. Unfortunately, that's not how that works. Language is nothing if not a shared thing.

Words do not possess a meaning intrinsic to themselves separate from that of who hears it; the only sense in which a word can 'mean something' is 'to someone'. Internally, anyone is free to interpret anything however they wish, but the whole point of language is that the speaker intends to communicate some specific concept to the listener, and chooses the words they believe will most likely result in that interpretation being the one that happens. The more well-chosen the words, the closer the speaker's and listener's interpretations of the word align, while poorly chosen words lead to interpretations that differ.

If two parties hold different interpretations on what something should mean, there is no shared meaning. They are free to explain and argue ("No, this is what that rule means") or even coerce ("well if that's how you think rogues work, I don't want you at my table") to try and come to some agreement, but until and unless they do, there is no shared meaning.

If all you want to do is interpret something to mean whatever you want it to mean, there's nothing stopping you, but when it comes to the meaning of a rule to be applied at the table, the only interpretation that matters is the one that the table agrees on.

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What did the developers mean?

It also requires making a judgment on developer intent, looking at the printed rules with the understanding that they were written by a person attempting to convey a concept, asking "what did they mean?" and as a result considering the possibilities of what the developer could have intended the rule to mean to the players - former interpretation, latter interpretation, or ambiguity.

We can immediately rule out the possibility that the meaning intended by the developer was the ambiguity, simply because the idea that the developer wants to confuse us as to how this works is a bad faith argument in the first place.

We can look at the fact that there is such a limit on NINE spells in the first place, as well as the limit itself and how it thematically dovetails with the subclass - that of an adventurer already relying on stealth, agility, guile, and quick thinking, and given the chance to enhance their skills with magic, choosing such that allows them to exploit their existing strengths and style of fighting - to see that the developers intended clearly enough for the lion's share of an arcane trickster's spells to focus on their existing abilities, hence the restriction to mostly IE spells. If an arcane trickster made IE spells the minority of their known spells, that would break the idea of the subclass.

(Exactly how tight the restriction on NINE spells should be is a good question, and you mentioned that you'd considered it. But it's a finer detail than this section covers.)

The idea of the former interpretation being the developer's intention also goes against one of D&D 5E's commonly cited design goals as a move away from the comparatively legalistic 3E, and the former interpretation is exceedingly legalistic and not at all obvious without the key meaning.

Even this question in an earlier edit called the former interpretation "an exploit", and even in its current state, presents the latter interpretation first and doesn't so much explain as it does pitch the former interpretation afterward. Those wordings presuppose that the latter interpretation is the one intended by the developers.

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A better write-up

The common interpretation that I have heard is that you are permitted one NINE spell known at 3rd, two at 8th, three at 14th, and four at 20th, and that no amount of retraining will raise that cap. (You could multiclass, but I'm scoping this to just your arcane trickster spells.)

If you're looking for a rewrite of the feature that makes it unambiguously so, try this (changes in italics):

Spells Known of 1st Level and Higher

You know three 1st-level wizard spells of your choice, two of which which you must choose from the enchantment and illusion spells on the wizard spell list.

The Spells Known column of the Arcane Trickster Spellcasting table shows when you learn more wizard spells of 1st level or higher. Each of these spells must be an enchantment or illusion spell of your choice, and must be of a level for which you have spell slots. For instance, when you reach 7th level in this class, you can learn one new spell of 1st or 2nd level.

Your focus on agility and stealth shapes your approach to your magic. Your spells known from this class must be of either the enchantment or illusion school of the wizard spell list, with the exception that at most one of them may be of any other school. This limit of spells known of other schools increases to two spells at 8th level, three at 14th level, and four at 20th level.

Whenever you gain a level in this class, you can replace one of the wizard spells you know with another spell of your choice from the wizard spell list. The new spell must be of a level for which you have spell slots, and cannot exceed your limit of spells known outside the enchantment and illusion schools.

Answer 4

Probably not, because "the spell you gained" can change

First of all, although your question is being downvoted into oblivion at the time I'm typing this, I applaud your clever idea! It's an interesting and careful reading of the rules. Naturally, this is definitely not what the rules intended, but it's worth asking whether or not it is actually what they say.

Now that being said, there is a serious problem with your strategy.

Our meaning of "replace" must remain consistent

Imagine a more typical scenario, where someone does the following upon reaching levels 3, 4, and 5.

• Level 3: They learn the spell Find Familiar (conjuration)as one of their three spells.
• Level 4: They choose to replace the spell Find Familiar with Shield (abjuration), because they can "replace the spell... learned at 3rd... level from any school of magic" (PHB, p. 98 post errata).
• Level 5: They want to replace Shield with Fog Cloud (Conjuration).

Now, as a DM, would you allow your player to do this proposed Level 5 step? Hypothetically, you could object that the spell "learned at 3rd level from any school of magic" was Find Familiar, and as such, could claim Find Familiar is the only spell eligible for being replaced with spells from any school of magic. You could make that objection. But would you?

If you see the questions above and answer "no, they can't replace Shield with Fog Cloud," then you are free to interpret RAW as you proposed in your question. But I suspect you likely would allow the level 5 proposed replacement to proceed! And this would imply something important: for the purposes of the rules, when you "replace" a spell you learned at 3rd level, the new spell becomes "the spell you gained at 3rd level." It doesn't go back in time and change your choice, but it "replaces" the previous spell in any context that the rules refer to it.

This curtails the method of replacement you proposed in your question. If you chose Illusory Script at 3rd level (as your unrestricted spell), you'd certainly be able to swap that out for a "NINE" (non-illusion, non-enchantment) spell at level 4 (for example, Find Familiar). However, from that moment on, Illusory Script is no longer eligible for replacement with a "NINE" spell: Find Familiar has taken its place in that eligibility, along with taking its place amongst your known spells. Henceforth, you can replace Find Familiar with any other Wizard Spell (that you have spell slots to cast) when you level up, but Illusory Script must be replaced by another Illusion or Enchantment spell.

This interpretation relies on some assumptions

It is worth nothing that the assumption that a NINE spell can be replaced more than once (e.g. from Find Familiar to Shield to Fog Cloud) is not necessarily a given. There are instances in the rules where spells learned with few restrictions cannot be replaced later with similarly unrestricted spells. For example, Bard spells learned through Magical Secrets are learned without restriction to class, but there are restrictions on how they can be replaced.

So to reiterate, if you (as a DM) would not allow a NINE spell to be replaced more than once, then your proposed reading of RAW is consistent and reasonable. However, if you would allow such a replacement, it will mean you need to acknowledge that your proposed strategy violates your own interpretation of RAW.