Is casting unused spells in the morning legit?

Question

Our group has a habit of casting spells in the morning before ending our long rest, to use unused spell slots, we call it "casting down" spells. Typical spells we cast are those with longer durations like mage armor and aid to buff us for the upcoming day without consuming any of the coming day's fresh spell slots. We also use it for divination spells like scrying.

I mentioned this in a recent exchange about the merits of aid, which I think is a great spell as it can be upcast to give party members 15-20 temporary hits in this way, and was told this was shenaniganry, which made me think: is what we do in any way not conformant with the rules? Is it unsavory?

Looking at the long rest definition, it states (PHB p. 186):

A long rest is a period of extended downtime, at least 8 hours long, during which a character sleeps for at least 6 hours and performs no more than 2 hours of light activity, such as reading, talking, eating, or standing watch. If the rest is interrupted by a period of strenuous activity - at least 1 hour of walking, fighting, casting spells, or similar adventuring activity - the characters must begin the rest again to gain any benefit from it.

So as far as I can see it is entirely legit to sleep for six hours, maybe hold watch for 2 hours sometime in between, and in the morning before officially ending the long rest, cast spells for less then one hour, then resume the rest and end the rest at which time spell slots are regained.

If casting spells during a long rest is technically possible has also been answered here, with yes. But is doing that at the end of a long rest purely exploiting a technical loophole in the rules or can it be a legitimate use of rules from a narrative perspective, for the characters in-game?

Am I missing something?

Answer 1

Fine if it works for your table.

What you described fits within the rules as written, and if it works for your table, it's "legit".

Is it legal

You cited the rules of a long rest. What you described mechanically fits within the definition of a long rest, or can be trivially jiggered to fit. If you start your rest at fantasy-2200 and end it at fantasy-0600, if you spend t time at, say, fantasy-0500 casting spells, then as long as you extend the long rest past fantasy-0600 by t, and t is less than an hour, then you're good.

See also this question: Can you cast a spell just before the end of a long rest?

Counterpoint:

An argument that this technique is not even within the rules is that the phrase

If the rest is interrupted by a period of strenuous activity - at least 1 hour of walking, fighting, casting spells, or similar adventuring activity - the characters must begin the rest again to gain any benefit from it.

is equivalent to "if the rest is interrupted by any one or more of these things: a) at least 1 hour of walking, b) fighting, c) casting spells, or d) similar adventuring activity then the characters must begin the rest again to gain any benefit from it."

If this is correct, casting even one spell invalidates the long rest.

However, to my reading, the quoted passage is equivalent to: "If the rest is interrupted by a period of strenuous activity, the period being at least 1 hour, and being composed of one or more of the following: a) walking, b) fighting, c) casting spells, or d) similar adventuring activity - then the characters must begin the rest again to gain any benefit from it."

But you aren't asking if it fits within the rules. You're saying given it's accepted practice in your game, is it "legit".

Is it legit

You used legit in two different ways in your question. One meant conforming to rules-as-written. We've covered that.

I think you summed up your question well at the end:

But is [casting spells] at the end of a long rest purely exploiting a technical loophole in the rules or can it be a legitimate use of rules from a narrative perspective, for the characters in-game?

So in this case you mean "legit" as not just conforming to the rules technically, but conforming in a broader sense, as opposed to "shenaniganry", exploiting a technical loophole in the rules that has no narrative support in-game, that conforms to rules as written but in some sense violates rules-as-intended.

The rules are abstractions

The rules are abstractions. We use the rules to provide structure to shared story-telling. There are many, many places where if you closely examine the rules, they fail to create a perfect simulation of a fantasy world. For example, the concept of a long rest itself does not bear minute examination, as a simulation. For instance, is it really realistic that 8 hours works, but 7 1/2 don't? That 57 minutes of fighting only requires extension of the 8 hours by 57 minutes, but an hour and 2 minutes of fighting requires the 8 hours to begin again?

The characters don't know the rules

The characters don't know the rules, right? (Although for another perspective, see OOTS.)

So, if your characters say, "wow, let's use up the last of our spell slots, we've got 5 minutes before the end of the long rest", some might say you are exploiting a technical loophole in the rules that has no narrative support in-game.

It is easy to see how that could be considered to be a violation of rules-as-intended, or shenaniganry.

However, it is not unrealistic at all to imagine that the characters, knowing magical combat is likely, would want to prepare as well as possible.

The narrative gap

So, that leaves us with a narrative gap, between the static rules, and the imagined world of the game. We constantly bridge the narrative gap, any time we imagine what characters do, that fits within the rules. The character swings a sword, the player rolls to-hit. We fill the narrative gap by imagining whatever level of detail or narration to that sword-swinging that we want.

Bridging the narrative gap

The game is very broad in its support for how to bridge the narrative gap. There are no specific rules requiring how the narrative gap must be described, or that everything be justified in detail. In the Introduction, the Basic Rules describes How to Play:

1. The DM describes the environment.
2. The players describe what they want to do.
3. The DM narrates the results of the adventurers' actions.

The rules do not specify a narrative quality to the descriptions and narrations. It is just as RAW to say "we take a long rest" as to say, "we bed down for the night".

When a player says "we take a long rest", the players are free to interpret that as that the characters are saying "wow, it's getting late, let's get some shut-eye."

Who decides

The players (and DM) of the game decides what makes sense for that particular game. Third parties can offer an opinion, often a valuable one, but in the end what matters is your game.

In one game, a player may say, "before the end of the long rest, I cast aid to use up a spell slot", and the DM says, "sure, that works, you don't even need to tell me."

In another game, the player may say the same thing, and the DM says, "yeah, that won't work. The mechanics of the long rest are an abstraction. There isn't a moment when you know you have so many minutes left before the long rest ends."

Both are correct. Both are RAW. It is up to the those participating in the game to bridge the gap from the rules to their game.

Everyone at the table need not even completely agree, or even necessarily imagine it working exactly the same way. The DM makes a ruling and you move on.

A narrative solution

If you need a narrative solution to your quandary you can easily invent one.

For instance:

It had been a nervous night, but fortunately the party had been able to get some rest. Ricq had seen something moving off in the distance, but it didn't close on where the party rested in the hut. As she did every morning, Wendy held her crystal and closed her eyes, and felt for the power within. Like breathing, yesterday's power was being exhaled from her psyche, and once that breath was exhaled, today's power would come flooding in. With the last of the exhalation, Wendy summoned the arcane not-images of mage armor to her mind's eye, and repeating the familiar words and gestures, felt the familiar force settling about her. She remained still a few moments, and then felt the power flooding back into her. With a physical exhale, she opened her eyes, ready to face the day.

This is just A way to visualize the in-game narrative, supporting using yesterday's spell slots before regaining today's. This isn't RAW, it isn't RAI, it isn't how I play, or a recommendation. It's just an example showing that the narrative could support the rule.

So, who's to say exactly how it all works in-game? The players of the game. If it works for you, go for it.

Answer 2

Spellcasting interrupts any rest

According to the Sage Advice, spellcasting is a "strenuous activity". Casting a spell interrupts a rest:

Does casting a spell while taking a short rest interrupt the rest?

Yes. Spellcasting is more strenuous than the activities listed on page 186 of the Player’s Handbook: “eating, drinking, reading, and tending to wounds.”

The rules mention different kinds of "strenuous activity", casting spells included:

the rest is interrupted by a period of strenuous activity — at least 1 hour of walking, fighting, casting spells, or similar adventuring activity

So just walking is fine, but at least 1 hour of walking counts as an "adventuring activity". However, fighting is an "adventuring activity" regardless of its length. This seems plausible, since a 600-round combat is nonsense, and any spellcasting is described as "physically and mentally taxing" in the rules.

Here's a question about this ambiguity: Does a short combat or casting one spell interrupt a Long Rest? The answer implies different reading (1 hour of fighting, 1 hour of spellcasting, etc.) but is unofficial — it's based on Mike Mearls tweets, not Sage Advice neither the rules. Your GM might stick to the latter reading, there is nothing wrong with that. In this case any spellcasting will interrupt a long rest.

Answer 3

It isn't technically against the rules, but it is metagaming and is narratively dubious.

You've outlined the relevant rules. From a strictly rules focused perspective, this works. But this only works because you, the player, know the rules. What you're doing make no sense at all in the context of the narrative. Why?

Alright guys, it's morning, time to cast a bunch of spells because our spells recharge in five minutes.

This doesn't make sense because of what spell slots are:

Regardless of how many spells a caster knows or prepares, he or she can cast only a limited number of spells before resting. Manipulating the fabric of magic and channeling its energy into even a simple spell is physically and mentally taxing, and higher- level spells are even more so.

Casting spells is physically and mentally taxing, and doing it a bunch and then feeling totally refreshed five minutes later is nonsense. You don't spend 8 hours feeling invariably tired, and then the moment 8 hours is up go from feeling totally beat to feeling totally refreshed. Sure, that's how the rules look at it, but the rules are trying to make things simple. This business you call "casting down" just doesn't make any sense in the context of the narrative. It is 100% metagaming.

Now, metagaming isn't good or bad. If everyone is okay with doing this, then do it. It's fine.

Answer 4

You're using the dissonance between narrative continuity and mechanical discreteness

Since D&D is a game played with pen and paper (or digital equivalents), many things that happen gradually in real life are modeled as discrete events in the game. The recovery of resources at the end of a rest is one such example. Within the fiction, logically you are spending the entire rest gradually recovering the resources you have expended throughout your adventuring day (hit points, spell slots, etc.). However, in mechanical terms, all of that "gradual" recovery actually happens in a single instant at the end of the rest. This disconnect between the fiction and the mechanics is a necessary simplification, to make resource tracking tractable for pen & paper. (For example: do you really want to sit there gradually regaining 1 hit point at a time, erasing and rewriting the HP on your character sheet each time?)

So when you intentionally wait until 7.9 hours into the rest to expend the last of your resources, you are taking advantage of the fact that gradual recovery from a rest is modeled as instantaneous recovery for the sake of simplicity. Mechanically this works fine. The reason it feels questionable has nothing to do with the mechanics themselves. Rather, it's because you've discovered a corner case in the rules where they diverge unusually far from the narrative and proceeded to squeeze out a mechanical advantage by pushing on that corner. Ultimately this is not a question of whether this trick of casting spells right before the end of a long rest is mechanically allowed. The question is whether your group finds it to make enough narrative sense, or they feel it breaks the verisimilitude of your game. If the players and DM all agree that it's reasonable to do this trick and that they have more fun when it's allowed, then nothing in the mechanics stops you from doing it.

For what it's worth, my personal preference is to avoid taking advantage of corner cases arising from imperfect modeling of a real-life process by simplified rules. So I would generally say that as long as my character is resting and not interrupted by anything external, then they will not do anything on their own to interrupt their rest.

As a DM, you could disallow self-interruption

If you're a DM and want to disallow this trick, there's actually a fairly simple way to do so by slightly changing how you interpret "interrupted" in the following rule:

If the rest is interrupted by a period of strenuous activity - at least 1 hour of walking, fighting, casting spells, or similar adventuring activity - the characters must begin the rest again to gain any benefit from it.

You could rule that an interruption is defined as an external event that happens that demands a response from the resting characters. (More directly, it's an event initiated by you, the DM.) In particular, a character cannot interrupt their own rest. If a character voluntarily stops resting and engages in strenuous activity without any external reason to do so, then they have not interrupted their own rest, they have stopped resting, thus forfeiting any benefits from an incomplete rest. This ruling still allows your players to sling spells around when their camp is ambushed by goblins in the middle of the night, but it discourages things like "casting down" immediately prior to the end of a rest.

Answer 5

Technically legal in 5e, but...

You might be interested to hear of this rule in D&D 3.5e:

If a wizard has cast spells recently, the drain on her resources reduces her capacity to prepare new spells. When she prepares spells for the coming day, all the spells she has cast within the last 8 hours count against her daily limit.

There's a similar rule for divine casters.

D&D 5e does not have this rule. Was the rule omitted out of a general desire for simplicity, or because the designers wanted to enable the spellcasting trickery your group is doing?

Either way, what you're doing is legal. But, if your DM wanted to stop it, one way to do that might be to adopt this rule from the older 3.5e system.

Answer 6

Is it RAW?

It is weird I never noticed this before, but it looks like this is RAW. As long as your total time casting spells or doing any other non-restful activity doesn't exceed 1 hour, it can be part of the rest.

Is it RAI?

As per one developers opinion here: Does a short combat or casting one spell interrupt a Long Rest? (credit to enkryptor's answer above), it appears it is allowed, RAI. The intent is that you need enough of an interruption that you give up on getting proper rest (at least 1 hour's worth). Basic spellcasting of simple one/round spells or even a combat encounter is not enough to stop the rest if you get right back to it

Is it fair/balanced?

I think it is. Most of the time, spells have pretty low durations and usually long rests are taken places far from combat, so many buffs would fall off before you use them anyway. Longer duration ones are the ones you would get benefit out of, but I think they are few enough of them that it should be fine, especially since most long duration buffs are concentration anyway.

How does this compare with previous editions?

In previous editions, there were specific things each casting class had to do to get their spells back each day. They didn't even necessarily need to sleep anywhere near the time they do this. For example, a cleric needs to pray to their god for 10 minutes I think it is in 3.5/pathfinder once/day to get their spells back. Depending on your god, this might be done in the evening, the morning, or even noon. As such, if you typically sleep at night and pray to get spells back in the morning, you could cast the previous days spells before praying for the new ones. This was pretty much expected, especially since in 3.5/pathfinder, you don't full heal just by resting, so casting healing spells before getting your spells back was expected.

Conclusion

This looks to be legitimate. If it works for your table, keep doing it. Of course the GM always has the final say.

Answer 7

You have the right paragraph up,

...at least 1 hour of walking, fighting, casting spells, or similar adventuring activity

Although it is vaguely worded, I think the way to interpret it isn't that it is one hour of any of the activities on the list, it is one hour of walking or any amount of fighting, casting spells etc.

Therefore I would say casting your spells end the rest by being strenuous activity

Answer 8

I'm going to add something here that seems very obvious to me, and use Artificers as an easy reference. Artificer's make for an easy reference because for them spell slots isn't "how much magic power do I have in me?" but is rather "How many of the thingymajigs did I build?" That could be regarded as over-simplification, but humor me.

If you cast spells at the end of a long rest, for the new day, those are the first spellcasts of the new day, using the new day's slots. If you cast them at the beginning of the rest, they are the last casts of the prior day, using the prior day's slots. And to be clear, I'm not talking immediately before or after the rest, I'm talking during the rest, but towards which end of it. Though if we go with the commenters who suggested a reading of the rules where you can't cast spells during a rest without interrupting it anyway, then it would have to be a before/after matter.

If an artificer casts some spells at the beginning of a rest, they are using the last of the devices they built the night prior, before going to sleep or sitting down to make a new set of devices. But if they cast spells at the end of the long rest, before it technically ends and the party sets out, the artificer had already finished building all their devices, and the spells are cast by using some of the new devices from the new days set. I said the word "devices" too many times.

Skipping the part about standing a watch if warranted, imagine the process of the long rest as being once in their room at the in or after camp is set up, the artificer winds down from the day's excitement, shifting mind and body into a more tired/sleep ready state, by doing the monotonous and relatively boring activity of making their devices, and then they go to sleep after they've been lulled by doing so. Casting spells at the end of the rest, i.e. in the morning, would be using what they built before they went to sleep, the new days spell slots, not the remaining ones from the day before. Additionally, since the spell slots represent the maximum amount of devices the artificer can have ready at once, they can't have made and used extras there are no free casts, long rest or not the spell must use a slot from one day or another, without the max available being exceeded.

EDIT: I forgot I wanted to add the additional question of spell preparing. So for a sorcerer who just has a set set of spells, the question here is just "can I cast this at the end of a rest and still have the slot?" But for, say, a cleric who as a whole bunch of spells and can prepare a few of them, when is preparation determined? Like, if my group/dm decided we could cast spells at the end of rest, could I cast Aid, but then not have aid prepared that day?