D&D General Why is the multi-classing spell slot math so weird?

[Silam]

Consider Alice, a character who is an Eldritch Knight 7. They get 4 level 1 slots, and 2 level 2 slots. If that character then becomes a Wizard 1, the multi-classing rules say that their slots are now determined by their full Wizard level + a third of their EK level (rounded down). 1 + 7/3 rounded down = 3; which provides 4 level 1 slots, and 2 level 2 slots. And therefore, their Wizard level, which is a full caster class, gives them exactly 0 extra slots.

Consider Bob, another character who is an Eldritch Knight 9. They also get 4 level 1 slots and 2 level 2 slots. If that character becomes a Wizard 1, then the formula gives us 1 + 9/3 = 4; which provides 4 level 1 slots and 3 level 2 slots.

I'm not looking for an explanation of what rounding down means. Obviously I know that. I just find it weird that if we considered the "1/3 rounded down math" on the pure EK7 (Alice, before multi-classing) in isolation, we would arrive at the result that they are a 2nd level caster, and therefore get 3 level 1 slots and 0 higher level slots. But instead of that, the pure EK effectively rounds up their caster level to 3 for the sake of their slots (and spells known). So going from the pure EK to the multi-classed EK/Wizard, the contribution to spell slots from the EK transitions from rounding up to rounding down.

It's not a big deal per say. I don't think it breaks balance or anything. It's just weird that taking a level of a full caster class does not actually improve the character's ability to cast (beyond extra spells known/prepared) for Alice, but it does for Bob. It's also weird that, in a sense, becoming a wizard results in a slight nerf to what the EK in isolation contributes to the build (due to the rounding direction getting flipped).

The phenomenon can be explained away, e.g., "The years of learning magic as a hobby made Alice sloppy, and some of the shortcuts and assumptions accumulated along the way had to be unlearned when wizardry became their main pursuit. Bob on the other hand had no such trouble and the transition into wizardry as a focused endeavour came quite naturally."... but like, why is Alice getting shafted while Bob is just fine? It's just weird, IMHO

 

[TwoSix]

It IS weird. The root cause is the "round down" rule, which causes the discrepancy because the actual single class progression for partial casters (1/2 like rangers and paladins, or 1/3 for EKs and ATs) rounds up.

Most games I play with using bog-standard 5e use Beyond, so it hasn't come up in quite a while. Since Beyond handles the calculations, no one really notices. The one time I had it come up at the table (I think it was a paladin 5 going into sorcerer who complained about it), I simply let them round up for the slot calculation.

 

[aco175]

So if Allice was a 7th level wizard first and then took levels in fighter to become an EK she would get 1 first level spell being a 3rd level fighter? Makes more sense this way.

I tend to say that if you want to multiclass, you need to be able to accept the problems.

 

[Silam]

So if Allice was a 7th level wizard first and then took levels in fighter to become an EK she would get 1 first level spell being a 3rd level fighter? Makes more sense this way.

I may be missing something but I don’t understand what you mean here…

At Wizard7/EK3, the effective caster level would be 8th, which would provide an extra 4th level spell slot compared to the previous level. That scenario seems fine to me?

 

[Umbran]

It's not a big deal per say. I don't think it breaks balance or anything. It's just weird that taking a level of a full caster class does not actually improve the character's ability to cast (beyond extra spells known/prepared) for Alice, but it does for Bob. It's also weird that, in a sense, becoming a wizard results in a slight nerf to what the EK in isolation contributes to the build (due to the rounding direction getting flipped).

It is weird, but it also isn't.
Alice is at the bottom of that tier of spell slots, while Bob is at the top. The one level of wizard is enough to boost Bob into the next tier, but not enough to boost Alice.

Broadly, splitting one's attention doesn't usually grant direct boosts in power - the power gain is mostly in synergy.

 

[Laurefindel]

It IS weird. The root cause is the "round down" rule, which causes the discrepancy because the actual single class progression for partial casters (1/2 like rangers and paladins, or 1/3 for EKs and ATs) rounds up.

Most games I play with using bog-standard 5e use Beyond, so it hasn't come up in quite a while. Since Beyond handles the calculations, no one really notices. The one time I had it come up at the table (I think it was a paladin 5 going into sorcerer who complained about it), I simply let them round up for the slot calculation.

Don’t they all round up now (and therefore why rangers and paladins have spells at level 1)? The artificer used to be the only one that rounded up on multiclass, but don’t they all do so in 5.24?

 

[Silam]

Don’t they all round up now (and therefore why rangers and paladins have spells at level 1)? The artificer used to be the only one that rounded up on multiclass, but don’t they all do so in 5.24?

IIUC, by the RAW, all classes round up while pure, but the EK and AT transition to rounding down when multi-classing.

 

[Charlaquin]

Don’t they all round up now (and therefore why rangers and paladins have spells at level 1)? The artificer used to be the only one that rounded up on multiclass, but don’t they all do so in 5.24?

Half casters all round up now, but 1/3 casters still round down for some reason.

 

[Lazybones]

Perhaps the logic is because the first two levels in those classes don't grant spells? Paladins and rangers now grant spells at L1, so they round up.

 

[Sword of Spirit]

Getting to round up as a single class character versus down as a multiclass character is likely intentional. The point that it makes multi classing weird with certain combinations is a side effect that was likely considered a small trade off for favoring single class characters.

Personally, while I used to see multiclassing as essential to the D&D experience (especially pre-3e), I've come around to still loving the concept, but wanting to pretty much eliminate the mechanical implementation. My players almost never use it anyway. We had a rogue/monk once in a 20th level one-shot. We had a character that started as a 0th level fighter plus 0th level wizard before switching to some homebrew gestalt multiclassing I didn't end up liking. In our main campaign our rogue had taken a level of sorcerer. And I had actually suggested to my friend that his bard should take 1 level if wizard to do what he wanted to do.

I eventually decided that anything that someone wanted to do conceptually with multuclassing (as opposed to purely mechanical intetactions) either could already be done with the rules, or I would make rules to allow it.

Many classic combos work more or less out of the box or with feats in 5e. Anything + rogue works with just skills, tools, and proficiencies unless you see sneak attack as essential to the concept. Fighter + cleric is as easy as War Domain (or another heavily armed option) + cleric. A cleric/wizard can be one of the classes + magic initiate and ritual caster for the other (doesn't work for all concepts).

The rogue player just decided she wasn't satisfied with the dip and retconned it to the Magic Initiate feat (which I buffed to also allow usage of magic items as spellcasting foci as the class).

I made an Arcanist's Spellbook feature for the bard that lets arcane casters trade two of their known spells for flexible spell slots they prepare from a book like a wizard. That killed two birds with one stone, since it seems hardly anyone plays prepared casters in my group, and I miss seeing spell preparation.

Fighter + wizard works with Eldritch Knight or Bladesinger if you want to lean strongly to one class, but not so well as a more evenly mixed hybrid. After the unsatisfying experiments over the years I finally came up with Warrior-Mage class that I'm really happy with. Full caster without the extra features of a wizard, d8 HD with medium armor and martial weapons. Extra attack, War Magic, and then mostly subclass features. The three subclasses are Elven Fighter-Wizard (for the most iconic MC combo), Gish (for actual githyanki gish or githzerai zerth feel), and Planetouched Champion (for that Planescape fighter-mage aasimar, tiefling, and genasi feel, and a dash of the 3e planar champion prestige class).

If someone ends up with a multiclass concept they like that isn't well supported in the rules (and feels appropriate to me) I'll just make a feat(s), a subclass, or if absolutely needed a full class (though I can't think of any others that are really necessary for classic combos).