game design – Mana, Backlash and Slots: how to limit a magic system

Generally, I encountered three big systems for limiting the amount of magic that characters can wield at a given time in my RPG career. Grossly simplified they belong to one of three groups: Mana-Systems, Backlash-systems, and Magic Slot-allotments. Of course these come at different names in other systems, but their ideas are there

Pay the Price-Systems aka “Mana” et al.

Mana systems generally come with a set number of magic points that can be spent on spells. Most spells take several of these points and balance the used amount with the power of the spell: the more powerful, the more points it takes. For example the-dark-eye-4 uses that approach. In call-of-cthulhu your price is sanity, making it almost-mana, and the life or stamina of a character also can step in as mana replacement in many other systems.

I think they offer a huge variety, as you can drain that mana pool with a huge variety of setups, but their main drawback is bookkeeping.

When most spells only cost a single point an that is not linked to a vital statistic, the system becomes pretty much a Magic Slot.

Magic-Slots

Magic-slots usually represent a single cast of a (baseline) spell. This makes tracking easier, no matter if you need to choose your slots first (as a dnd-3.5 wizard needs to) or can spend them willy-nilly as a l5r-4e shugenja. The downside I see is that we don’t get the same balancing fine thread screw as in a Mana-system but at increased usability.

Some variants also allocate levels to slots to try and balance the power of spells to their usage.

Fighting the Backlash

A totally different approach is gone in shadowrun: you can cast as much as you want, but each spell kicks you in your shins and can damage you. The premise here is, that magic has a Price of Power (TV-Tropes warning) – but there is a mechanic that allows you to resist that damage. It is somewhat related to Mana-systems in that you pay for magic with a statistic (typically health, stamina or sanity) but got a chance to resist that loss.

The downside here is clearly increased rolling but at the benefit of occasionally more magic. Or less. Or actually giving magic a proper risk.

The Balancing act

Now, with the basis out of the way:

What design maxims should determine a choice between those three systems (or alternatives)?

Are there inherent factors that make a magic-limiter system fit better to a specific approach to designing a game than others or does a specific magic-limiter system grow naturally from a specific approach to gaming?

Example questions that might help to answer what counts as a design maxim for this question:

  • Might X-system better suited for a simulatoric/dynamic/whatever approach to designing an RPG than a Y-system?
  • Can a goal of how the game is to be played or what stories should develop be the factor to decide what kind of system to choose?
  • Might dice/game mechanics make one system a superior choice over others?
  • What considerations in streamlining the game mechanics can sway the needle between magic-limiting mechanics?

dnd 5e – Are the spells learned from the “Touched” feats considered class spells when cast using spell slots?

The Fey Touched and Shadow Touched feats published in Tasha’s Cauldron of Everything each grant the use of two spells. Among other things, they say:

  1. You learn the (spells).
  2. You can cast each of these spells without expending a spell slot (once per long rest).
  3. You can also cast these spells using spell slots you have of the appropriate level.

The spellcasting ability for these spells is specific to the feat, so it may or may not be the same as the ability of a class that grants spell slots.


Casting classes all have their own quirks regulating their spellcasting features, but these shouldn’t be relevant to how the Touched feats’ spells are cast in #2 because that casting isn’t using a spellcasting feature. This is clear because even non-casting classes can cast the spells in this way, so only the generic spellcasting rules apply there.

(This is related to why racial feat spells can’t be cast with a focus, as discussed at If a spellcaster’s racial trait grants a spell that requires material components, can they use their class’ focus to cast that spell?)

However, things get more complicated when the feats’ spells are cast as described in #3, because the spell slots referenced there do come from a class spellcasting feature. In that case, does the caster simply use the spell slot as “fuel” and otherwise cast the spell exactly as it had been cast for #2? Or is this inherently different, with the caster actually using their class spellcasting feature and therefore having to follow all of its specific rules?

Furthermore, is the answer different depending on whether the specific Touched feat spell being cast is on the caster’s class’ spell list or not?


Potentially Related:

Does Magic Initiate allow the chosen spell to effectively be “always prepared” if the spell is on their spell list?

What makes a spell being cast considered to be a {class} spell?

Are spells learned from feats considered to be associated with your class?

dnd 5e – What happens if a character takes the Thief of Five Fates invocation, but doesn’t have Warlock spell slots?

The text of the Eldritch Invocation is pretty clear…you can cast bane using a Warlock Spell Slot.

If you don’t have Warlock Spell Slots, you cannot cast it. This same rule applies to a multi-classed Warlock: they have to use a Warlock spell slot for this, they can’t use a normal spell slot that they acquired from, say, Multi-classing Sorcerer.

The language used across these Eldritch Invocations is very consistent. If it was intended that you could cast these spells using some other Spell Slot, then it wouldn’t specify that you had to use a Warlock Spell Slot. It would instead say something like…

You can cast bane once using a spell slot.

But it doesn’t. It would have been very easy for them to leave the specificity out, and they did not. Thus it’s a safe bet that this is intentional.

This is supported by an interview with Jeremy Crawford (lead rules designer for WotC), found here. To transcribe…

Bart Carrol: “So, for example, if it requires a warlock spell slot, then in that case it would require a warlock to be able to use it?”

J. Crawford: “What this feat is saying, is that it doesn’t matter what the prerequisite is. If an Invocation has a prerequisite of any kind, only a Warlock can take it”

While not a definitive ruling (as it’s just an interview, not a formal Sage Advice post), and is using Crawford’s usual circuitious language…I find this to be fairly strong support. Crawford appears to consider “you need a Warlock Spell Slot to cast this” to be a prerequisite.

dnd 5e – Why do Warlocks only have spells up to 5th level? What’s the correct progression for their slots?

The book is correct. For the reason why level 6-9 spells exist for the warlock when their Pact Magic slots cap at 5, check the Mystic Arcanum class feature on PHB p.108.

Mystic Arcanum

At 11th level, your patron bestows upon you a magical secret called an arcanum. Choose one 6th level spell from the warlock spell list as this arcanum.

You can cast your arcanum spell once without expending a spell slot. You must finish a long rest before you can do so again.

At higher levels, you gain more warlock spells of your choice that can be cast in this way: one 7th-level spell at 13th level, one 8th-level spell at 15th level, and one 9th-level spell at 17th level. You regain all uses of your Mystic Arcanum when you finish a long rest.

It’s simulating the once-a-day spell slots that other casters get (presumably, they didn’t want you recasting a 9th level spell every time you rested throughout the day), but there are a few minor differences.

  1. It’s not technically a spell slot for anything that cares specifically about spell slots (such as the feature below that in the PHB, Eldritch Master), as mentioned.
  2. Unlike most spellcasters, you only ever “know” (as an arcanum) one spell each of 6th-9th level.
  3. You cannot ‘upcast’ spells to those 6th-9th level ‘slots’, as they aren’t really slots. As an example, if you knew shatter as one of your usual Pact Magic spells, you could only cast it with one of your standard spell slots (likely a 5th level slot by the time you have Mystic Arcanum, barring other spell slot levels being available due to multiclassing or the like); you could not expend a use of Mystic Arcanum instead to cast shatter at spell level 6+.
  4. Similarly to point 3, you always cast the 6th level arcanum at 6th level, the 7th level arcanum as 7th level, etc. You could not, for example, upcast a circle of death chosen as your 6th level arcanum to your 8th level arcanum ‘slot’; that 8th level arcanum can only be used on whatever spell you chose for that level, such as glibness.

dnd 5e – Can I use Pact Magic spell slots gained on a short rest to gain sorcery points?

Yes, Flexible Casting doesn’t specify where the spell slot comes from, just that you expend one to gain points. This means that you can expend a spell slot that you have from Pact Magic to satisfy its requirement, and thus gain sorcery points from it.

And yes, this has been confirmed as the correct reading by Jeremy Crawford, the lead rules designer for D&D 5e, for exactly the use you’re asking about (though Crawford’s tweets are no longer considered official rulings):

Bill Cavalier @dungeonbastard · 6 May 2015
@JeremyECrawford Can a warlock/sorcerer covert warlock spell slots to sorcery points?

Jeremy Crawford‏ @JeremyECrawford · 6 May 2015
The sorcerer’s Flexible Casting feature is omnivorous, able to turn spell slots from any class into sorcery points.

Bill Cavalier‏ @dungeonbastard · 6 May 2015
@JeremyECrawford The use case is: convert warlock slots to sorc points, short rest, regain warlock slots. Turning a short rest asset to long

Jeremy Crawford‏ @JeremyECrawford · 6 May 2015
@dungeonbastard Yep, that works. Similarly, a paladin/warlock can use warlock slots for Divine Smite. Warlocks have so few slots on purpose!

dnd 5e – Is a Manual of Golems’ spell slot restriction covered by multiclassed spell slots?

There are many cases in which multiclassing spell slots can create unclear areas in the rules, but I don’t think this is one. The only requirement from the manual of golems is that you have at least two slots.

For multiclassing spellcasters slots are determined by your combined spellcaster level and do not belong to any one class.

Spell Slots. You determine your available spell slots by adding together all your levels in (spellcasting classes). Use this total to determine your spell slots by consulting the Multiclass Spellcaster table.

Looking at the table referenced, you see that a wizard 5/cleric 5 does indeed have two available 5th level slots. There is no differentiation in the rules that one of those slots is a wizard slot and one is a cleric slot. You can use those 5th level slots to cast any spell you know from either class.

Seeing that we do not need to differentiate where those slots came from (and the rules don’t differentiate them anyways), they would meet the manual of golems restriction with no caveats.

One confusing point might be that multiclassed spellcasters do indeed use their individual classes for one aspect in particular: determining what spells they know and/or can prepare.

Spells Known and Prepared. You determine what spells you know and can prepare for each class individually, as if you were a single-classed member of that class.

However, this is only the rule for determining what spells you know not how many.

So, while it is true that the cleric/wizard does not actually know/cannot prepare any 5th level spells (only upcast from lower levels), that should not matter in this case.

The manual of golems does not require a character to use or expend any 5th level spells or even spell slots to use the item. It only requires that they have them. And, as shown above, they definitely have the required number of slots.

The spell slot restriction on the manual of golems seems to be a restriction put in place to ensure that only powerful spellcasters can use it. Allowing multiclassed spellcasters to use it with combined slots not only follows the rules but also still abides by the presumed intent of the spell. Even though their spellcasting prowess is split between more than one discipline, they are still a very powerful spellcaster.

From a balance/rules perspective, multiclassing will never allow a character to be able to use this item before a single-classed full spellcaster would. In fact, many combinations will actually slow down spell progression meaning the multiclassed character would have to be a higher level in order to use it. This seems very straightforward, well within the rules, and fair.

dnd 5e – Can a Warlock use Pact Magic slots to cast spells learned from another spellcaster class?

Yes, you can use warlock slots to cast any spell you know. It’s in the PHB in the section on multiclassing. Page 164:

If you have both the Spellcasting class feature and the Pact Magic class feature from the warlock class, you can use the spell slots you gain from the Pact Magic feature to cast spells you know or have prepared from classes with the Spellcasting class feature, and you can use the spell slots you gain from the Spellcasting class feature to cast warlock spells you know.

The effect is determined by the slot’s level, as always in D&D 5e.

dnd 5e – Is there a RAW way to allow the PCs to recover only some of their spell slots, HP, hit dice etc?

This is a class feature of Wizards and Warlocks.

Wizards have a class feature called Arcane Recovery:

You have learned to regain some of your magical energy by studying your spellbook. Once per day when you finish a short rest, you can choose expended spell slots to recover. The spell slots can have a combined level that is equal to or less than half your wizard level (rounded up), and none of the slots can be 6th level or higher.

And the Warlock’s Pact Magic feature says:

You regain all expended spell slots when you finish a short or long rest.

So I would be quite hesitant to just give these class features to other casters for free.

Either give them a proper long rest or only a short rest, and adjust the difficulty accordingly.

I’ve run this both ways. I’m sure many DMs know what this is like: either your party blows everything early in your dungeon, or they play conservatively and it looks like the end of your dungeon won’t even be a challenge.

Here’s the thing: your players don’t know what tomorrow holds. You’re only having this issue because you’re the DM and you know what you have planned. So change your plans. If you don’t want them to get their spells back, adjust your encounters accordingly so as to be manageable, but still engaging. Or maybe you think they would better enjoy a significant challenge on a fresh set of spell slots. Adjust your encounters accordingly.

I’ve never implemented a half-rest sort of mechanic where every gets some of their spells back, so I won’t speak to how that might work, but I can say this: I’ve never needed to. I’ve had success both ways, either giving them a full rest or giving them nothing back. You just have to be flexible.

For what it’s worth, I see no reason from your description not to give them a proper long rest. A long rest requires 8 hours of down time and at least six hours of sleep. I’m usually somewhat flexible with those numbers, but the rules do not say it has to be good sleep.

dnd 5e – How many spell slots does a Level 3 Warlock have?

The explanation of spell slots is shown on page 107 of the PHB:

SPELL SLOTS

The Warlock table shows how many spell slots you have.
The table also shows what the level of those slots is; all
of your spell slots are the same level. To cast one of your
warlock spells of 1st level or higher, you must expend a
spell slot. You regain all expended spell slots when you
finish a short or long rest.

For example, when you are 5th level, you have
two 3rd-level spell slots. To cast the 3rd-level spell
thunderwave, you must spend one of those slots, and
you cast it as a 3rd-level spell.

So at 3rd level, you have 2 slots, you know 4 spells and you cast them as 2nd level spells.

dnd 5e – Is there a RAW way to allow the PCs to recover only some of their spell slots etc?

This is a class feature of Wizards and Warlocks.

Wizards have a class feature called Arcane Recovery:

You have learned to regain some of your magical energy by studying your spellbook. Once per day when you finish a short rest, you can choose expended spell slots to recover. The spell slots can have a combined level that is equal to or less than half your wizard level (rounded up), and none of the slots can be 6th level or higher.

And the Warlock’s Pact Magic feature says:

You regain all expended spell slots when you finish a short or long rest.

So I would be quite hesitant to just give these class features to other casters for free.

Either give them a proper long rest or only a short rest, and adjust the difficulty accordingly.

I’ve run this both ways. I’m sure many DMs know what this is like: either your party blows everything early in your dungeon, or they play conservatively and it looks like the end of your dungeon won’t even be a challenge.

Here’s the thing: your players don’t know what tomorrow holds. You’re only having this issue because you’re the DM and you know what you have planned. So change your plans. If you don’t want them to get their spells back, adjust your encounters accordingly so as to be manageable, but still engaging. Or maybe you think they would better enjoy a significant challenge on a fresh set of spell slots. Adjust your encounters accordingly.

I’ve never implemented a half-rest sort of mechanic where every gets some of their spells back, so I won’t speak to how that might work, but I can say this: I’ve never needed to. I’ve had success both ways, either giving them a full rest or giving them nothing back. You just have to be flexible.

For what it’s worth, I see no reason from your description not to give them a proper long rest. A long rest requires 8 hours of down time and at least six hours of sleep. I’m usually somewhat flexible with those numbers, but the rules do not say it has to be good sleep.