Variant Multiclassing v1.1 (AD&D/Gygax Style), help with play balance

[dmhelp]

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[OldTrees1]

Hmm
Cleric / Wizard 20 would be like a 16th level Wizard with a broader list and a couple more features. Seems reasonable or even a bit generous. So a reasonable T4 character.

Barbarian / Paladin 20 would be like a 24th level 5E warrior, which means a T3 character.

Fighter / Wizard 20 would be like a 16th level Wizard with plenty of new features. Not strictly stronger than a 20th level Wizard but definitely a generous multiclass.

All in all this would be a buff (well duh!) and will be an unequal buff, but your group might enjoy in nonetheless. And the imbalance stems from existing imbalance in the T3-T4 features of the classes, so I do not fault this variant for presuming the content that ought to be reasonably balanced is reasonably balanced.

[Yakk]

I think I can emulate this in a "5e" way that eliminates dead levels, gives you pseudo-gygaxian dual classing, and isn't far off.

1. You can multiclass at most 2 classes total.
2. You cannot gain a level in a class unless the other class is greater or equal to your current level. Once you start a dip, you have to level in the other class until they match.
3. No new multiclassing after level 10.
4. You gain features of each class, except HD, of that class level plus 1/2 the other class level, capped at twice the class level.
5. If you have two extra attack(2) features, you can bump one classes non-spellcasting features by 1 level.
6. You can choose to take extra attack (2) by swapping all level 3 non-spellcasting feature for it (you get level 3 feature at 5) if your total level is 5 or more and that class gets it.
7. For casting progression, the fastest advancing primary caster class. Add 1/2 of (other class + other class caster or pact magic levels/your primary class advancement rate). Those are your slots. (Mustic arcanum act like spells known and daily slots for this purpose).

So Barb 2/Fighter 3 can delay the fighter subclass for extra attack.

Fighter 10/Barb 10 can get extra attack(3) (has two copies of extra attack(2)).

Wizard 10/Fighter 10 has 15th level wizard casting.

Wizard 10/EK 10 is (10 +(10+3)/2)=16th level casting.

Sorcerer 10/Paladin 10 is (10 +(10+5)/2) = 17th level casting (but only 8th/4th level spells known).

EK 10/AT 10 casts as a (10+(10+9)/2)=19th level EK

Paladin 10/EK 10 casts as a (10+(10+6)/2)=18th level Paladin

Ranger 10/Paladin 10 casts as a 20th level ranger slots

Wizard 10/Cleric 10 casts as a 20th level wizard or cleric slots.

Warlock 10/Wizard 10 either casts as a 20th level pact or wizard, they pick.

EK 10/Wizard 3 (they switched to wizard at 10, dual-class style) casts as a (3 +(10+3)/2=9, capped at 6) 6th level wizard.

I think this emulates your gygaxian MCing. It gives a HD per level, half each class, forces an even split.

At 20 you'll usually get 6 ASIs (4,4,8,8,12,12), as ASIs are treated like class features here.