Thought Experiment: full caster progression, but very limited spells known

[Greywander]

I just had a thought experiment pop into my head. Let's say that we're playing in a special campaign where everyone gets full caster progression with regard to spell slots, but you're extremely limited on your spells known. Say, you only start with 1 spell at 1st level, and know perhaps 5 spells by 20th level. But, you can choose any spell. Let's ignore classes for now and assume that everyone has whatever weapon/armor proficiencies they need to make their character concept work, but no spellcasting beyond what's described here.

With cantrips, you get infinite casting, which is definitely appealing (especially at low levels when spell slots are limited). Good utility cantrips like Prestidigitation, Minor Illusion, Shape Water, Mold Earth, and a few others would probably see a lot of use. These allow you to do things you can't normally do. Fire Bolt is nice, but it's really just a punchy crossbow that sets things on fire. It's not something you couldn't already do, it just does it a bit better.

With so few spells, it's inevitable that you'll have spell slots for levels you don't have spells for. So it makes sense to take spells that upcast well. High level spells would only have limited casting, but it would still probably be worth it to have one for when you really need to do something impactful, e.g. to turn the tables when you're losing a fight. If all you had was 1st level spells, you'd get so many castings for them, since you wouldn't have anything else to spend your slots on. On the other hand, if you don't have any 1st level spells, then you're basically losing out on 4 castings.

The limitations here are what makes this interesting. Choosing higher level spells means giving up your lower level slots, since you have nothing to cast with them. Choosing lower level spells means limiting how much impact you can make in a single casting. You can spread them out, but you still can't take a spell for every level. And you probably still want a cantrip or two. The person who takes a 9th level spell can win the game in a single casting... if their spell succeeds. Whereas the person who opted to take an 8th level spell instead gets two chances for it to take hold, or can create the effect twice! Those who focus on low level spells and cantrips can win the game of endurance, so long as they survive long enough to use them.

There's a lot to consider here, things you wouldn't normally have to consider since you'd have enough spells known/prepared that you could just get everything you need. One thing is for sure, though: there would be a lot more creativity in how you use your spells, as they'd be the only tools you have. In a regular game, you'd often have a different spell that would solve whatever problem you're dealing with much easier, but without all those additional spells, you'd need to find a solution with whatever tools you have. A lot of "automatic picks" (e.g. Shield) are now less appealing, because as good as they are, there are other spells that you would find more useful.

Honestly, this makes me wonder how different the game would feel if casters had been built like this initially.

[False God]

Why not use spell points instead? It makes your known spells more flexible, and doesn't leave you with a situation where you have say, 4 1st level spell slots but no spells of value at that level.

If you have a very limited number of spells known, you end up with things like the AT and the EK, highly thematic spell-builds. The utilitarian caster does not excel in this game because he can't know enough spells to be able to prep for any situation. Instead you end up with "Fire mage" who brings Wall of Fire, a "water mage" who brings fog cloud, a "cooking wizard" who has food-related spells and can bring something like Grease to the table.

You kinda end up with an almost Pokemon (this is not to be derisive) or Genshin Impact setup, where everyone brings a specific spell-set to the table, but there is very little overlap.

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Frankly I think it would be far better game design overall to have highly restrictive (like, 10 spells known tops) but thematic casters.

[OldTrees1]

Any other source of spells known (Feats, Multiclassing, Race, Backgrounds, Magic Item) would be very tempting. However assuming none of those, I suspect a Cantrip, 1st level, 3rd level, 5-6th level, and 7-8th level spell to be the 5 spells known. I am making this guess based on 5E having some level gaps be bigger than others. Unfortunately the more limited a resource, the more pressure the player might feel to pick something effective.

[Greywander]

Why not use spell points instead? It makes your known spells more flexible, and doesn't leave you with a situation where you have say, 4 1st level spell slots but no spells of value at that level.

No, that's part of the point. You can choose to know nothing but 9th level spells, giving you a variety of options for how you want to destroy reality, but you can still only use one of them once per day. It would be intentional that all of your remaining spell slots are "wasted". The ability to cast a lower level spell using a higher level spell slot is one of the reasons you'd take low level spells. Switching to spell points would remove this handicap, allowing anyone to get an equivalent number of castings out of a higher level spell (i.e. fewer castings but for more value). With spell points, you'd have very little reason to take low level spells, outside of some very specific picks like Fireball or Healing Word or Shield. Using spell slots instead of spell points pushes up the value of low level spells, since the slots aren't being wasted.

Though I suppose low level spells also benefit from spell points. Hmm, in fact, they might even benefit moreso, since you can essentially convert a single high level slot into multiple castings of lower level spells. Maybe I judged this idea too soon.

Something like the Sorcerer's Font of Magic might be a good middle ground. You can convert a spell slot into spell points, but the spell points can't be used by themselves. You have to convert them back into spell slots to use them. This way, you can convert a high level slot into several low level slots, or vice versa, but due to how Font of Magic works you're always losing value when you convert. This still allows someone with low level spells to convert high level slots into multiple low level slots, and it allows those with higher level spells to convert several low level slots into a single higher level slot. Font of Magic also doesn't allow for the creation of slots higher than 5th level, so you can't get multiple 9th level spells off like you could with spell points*, but it does allow you to convert a 9th level slot into spell points.

*The variant rule for spell points does specifically forbid casting more than one spell for each level 6th and up. Even though high level casters actually do get two 6th and 7th level slots. But technically you'd have the spell points to blast off a few 9th level spells if it weren't forbidden.

If you have a very limited number of spells known, you end up with things like the AT and the EK, highly thematic spell-builds. The utilitarian caster does not excel in this game because he can't know enough spells to be able to prep for any situation. Instead you end up with "Fire mage" who brings Wall of Fire, a "water mage" who brings fog cloud, a "cooking wizard" who has food-related spells and can bring something like Grease to the table.

You kinda end up with an almost Pokemon (this is not to be derisive) or Genshin Impact setup, where everyone brings a specific spell-set to the table, but there is very little overlap.

Yeah, this is what I'd expect as well. Don't forget, you can still do all the stuff a normal character can do. So you can still pack a crossbow or longsword, still use tools or make ability checks. So they wouldn't be wholly reliant on their spell picks for their identity, though spell picks would still be a core part of their character.

Frankly I think it would be far better game design overall to have highly restrictive (like, 10 spells known tops) but thematic casters.

I definitely understand wanting access to more spells. Honestly, that's one of the things about wizard that appeals to me. But I think you're right that the better game design would be more restriction. The problem is that so many spells go unused, because the opportunity to use that spell rarely comes up, and when it does, you often have another spell that works better. Fewer spells forces you to get the most mileage out of the ones you still have.

I think for the "knows all the spells" type of caster, that would work better for a caster built around using rituals. The trade off of having access to every spell (or at least a big chunk of them) is not being able to cast them at a moments notice; you need time to prepare. This works well with a utility caster, since you often have time to sit around while the ritual is being performed. It does kind of suck to be stuck plinking with a crossbow in combat, but if you're playing this kind of character it's probably because you're more invested in the out-of-combat stuff anyway. And if you can pull off a ritual Fireball or Web or what have you, you can use it to set up some nasty ambushes.

[loki_ragnarock]

Sounds like playing a Sorcerer. Take the metamagic feat and you're most of the way there, except on a different chassis.

Fey-Touched and the other one that has something to do with shadows would be even more valuable feats as they are one of the few ways to add spells known to a caster.

Paladins just got a hella bitchin' upgrade. Rangers did, too, but less so. For both of them this just means more slots faster, and their max five picks could be 6-9 level spells with their natural spells known rounding out every lesser.

[False God]

No, that's part of the point. You can choose to know nothing but 9th level spells, giving you a variety of options for how you want to destroy reality, but you can still only use one of them once per day. It would be intentional that all of your remaining spell slots are "wasted". The ability to cast a lower level spell using a higher level spell slot is one of the reasons you'd take low level spells. Switching to spell points would remove this handicap, allowing anyone to get an equivalent number of castings out of a higher level spell (i.e. fewer castings but for more value). With spell points, you'd have very little reason to take low level spells, outside of some very specific picks like Fireball or Healing Word or Shield. Using spell slots instead of spell points pushes up the value of low level spells, since the slots aren't being wasted.

9th level spells are inherently self-limiting. Ideally, you build this build not as though you magically popped into reality at 20th level, but brick-by-brick up until 20th level. So you'll always have lower-level spells, but what 20th level is giving you isn't really the 9th level spell you can use once, but the 9th-level spell points, to use the more mid-level but highly variable spells (IE: you've got a fire-mage "grenadier" who casts mainly Fireball but at various spell levels dependent on the situation).

Though I suppose low level spells also benefit from spell points. Hmm, in fact, they might even benefit moreso, since you can essentially convert a single high level slot into multiple castings of lower level spells. Maybe I judged this idea too soon.

This is really why I suggested it. Low and mid-level spells are highly flexible depending on your situation.

Something like the Sorcerer's Font of Magic might be a good middle ground. You can convert a spell slot into spell points, but the spell points can't be used by themselves. You have to convert them back into spell slots to use them. This way, you can convert a high level slot into several low level slots, or vice versa, but due to how Font of Magic works you're always losing value when you convert. This still allows someone with low level spells to convert high level slots into multiple low level slots, and it allows those with higher level spells to convert several low level slots into a single higher level slot. Font of Magic also doesn't allow for the creation of slots higher than 5th level, so you can't get multiple 9th level spells off like you could with spell points*, but it does allow you to convert a 9th level slot into spell points.

I dislike the need for extra steps, if it's 1-for-1, it's a pointiness middle step. If there's some degree of entropy involved, it's just extra math.

I'm not a fan of spell slots, and find point-based system more fun and flexible, which is why I recommend them at almost every opportunity. And you're going to need to provide casters who are highly spell-limited with some other form of flexibility. The current system provides high spell-knowledge flexibility at the cost of fixed spell-slot-casting. You cast low level spells because you HAVE to, not because you want to.

In a highly spell-limited system, you cast low or mid-level spells because you have the flexibility to do so.

*The variant rule for spell points does specifically forbid casting more than one spell for each level 6th and up. Even though high level casters actually do get two 6th and 7th level slots. But technically you'd have the spell points to blast off a few 9th level spells if it weren't forbidden.

Right, again the point of high level spell slots isn't the spells themselves. It's the points. Aside from that, the "best spells" IMO, are in the 3-6 range.

Yeah, this is what I'd expect as well. Don't forget, you can still do all the stuff a normal character can do. So you can still pack a crossbow or longsword, still use tools or make ability checks. So they wouldn't be wholly reliant on their spell picks for their identity, though spell picks would still be a core part of their character.

Right, much like the EK or the AT, spellcasting is still more this other thing you do, while the core identity of your character is being a sneak or a warrior or a hippy(druid).

I definitely understand wanting access to more spells. Honestly, that's one of the things about wizard that appeals to me. But I think you're right that the better game design would be more restriction. The problem is that so many spells go unused, because the opportunity to use that spell rarely comes up, and when it does, you often have another spell that works better. Fewer spells forces you to get the most mileage out of the ones you still have.

I agree. The trick is just to not "double up" and provide two casters with two different core themes (lets say, fire and electricity) with an identical spell (IE: Fireball and "Energy Ball"). Everyone is so specific that they all need almost completely different things, there can be stuff that's similar but it needs to be inherently different. IE: A Fire Mage's AOE would be damage(Fireball) but a Water Mage would be control (Fog Cloud), their 9th would be similarly similar but different, say "Rain of Fire" vs "Control Weather".

I think for the "knows all the spells" type of caster, that would work better for a caster built around using rituals. The trade off of having access to every spell (or at least a big chunk of them) is not being able to cast them at a moments notice; you need time to prepare. This works well with a utility caster, since you often have time to sit around while the ritual is being performed. It does kind of suck to be stuck plinking with a crossbow in combat, but if you're playing this kind of character it's probably because you're more invested in the out-of-combat stuff anyway. And if you can pull off a ritual Fireball or Web or what have you, you can use it to set up some nasty ambushes.

Rituals could also be much more variable, based on having multiple casters, the locations, or the specific ingredients. It would probably be much more roleplay and storytelling heavy though, so I'm not sure how well that would integrate into D&D.

[Kane0]

Minor note, DMG Spell Points doesnt let you cast multiple high level spells even if you have the points to do so. Its still one of each spell level 6th and higher per long rest, so actually fewer conpared to level 19 and 20 full casters who get additional 6th and 7th slots respectively.

Edit: anyways sounds like you would have much more room for actual class features on casters using this model (more like bards and warlocks than clerics and wizards) unless this is meant to plug into martials?

[Silpharon]

Some spells with excellent flexibility:

Damage:
Chromatic Orb (pick your element, pick your slot level, go-to single target damage)
Spiritual Weapon (force damage bonus actions, scales well at even levels)
Spirit Shroud or Guardians (easy concentration damage booster, scales well at odd levels)
Call Lightning (great multi-round damage output upscaled, use with Spiritual Weapon)
Shatter (AOE damage in a likely unresisted damage type that scales better than fireball at higher levels)

Healing:
Prayer of Healing (max health regen per a given spell slot)
Goodberry (for all the slots you don't use during the day to top people off - best on a Life Cleric, goto heal to pick up the dead instead of Healing Word)

Low level utility value meals:
Hex (if you attack a lot... lasts a long time upcasted and useful out of combat)
Bestow Curse (flexible.. concentration-less at higher levels)
Absorb Elements (scales well as a reaction)
Command (flexible, +1 person per spell slot)
Hold Person (+1 person per spell slot)
Find Familiar (there's so much a little buddy can do)

All the flavor stuff has got to be build specific, but here's a start at my high value spell list.