This is a very similar system to one the ones I was working on. What finally turned me against the simplicity of the XP split and advance, is that I think some things that worked well in AD&D don't work as well in 5e. Specifically, having less HD and being at a lower character level than others at the same XP total just is kind of a mess that I want to avoid. Another issue is that there wasn't a maximum level in AD&D, so although splitting XP would garner the same result at 20th level as in AD&D (the XP needed to make a 20th level wizard would make a 15th/15th fighter/wizard), in AD&D you could eventually go all the way up to 20th level and beyond (demi-human level limits, which would be houseruled for high level games with sane players anyway, aside). I
really like the hard level cap of 20 for 5e, and I'd apply that to the "ECL" of a split XP character too, leaving them forever at 15th level, which is sad.
But I really like the style of AD&D multiclassing, and hope to see a new and improved version come out for 5e.
The next system I came up with had you choosing an A and B class (I decided that making it possible to have three classes wasn't really necessary). You were an X-level character that was based on the level anyone else would be with your XP. Each class had base features it always provided, features it provided if it was the A class, features it provided if it was the B, and features it never provided as a multiclass component. Of the features you got, you got them at the same levels as the standard class for your A class, and at one level less for your B class.
This was messy, left you having to pick only one subclass (the B class provided one, the A class didn't), and required a separate write-up for each class.
The one I'm currently working on is a little simpler and is inspired by 4e's hybrid multiclassing. You pick two classes (from available combinations, which I tend to limit). A simple table tells you which proficiencies you get. You get the best HD. That was a hard decision, but I made it based on a couple of points. The first is that it is odd to specifically target HD as a feature to average, when most other features you just get the best of. (Although in this system, armor is more of an average.) The other is to preserve whether you are front rank, second rank, or rear rank combatant. I just don't like that a fighter/mage has less hit points than a fighter/cleric--it rubs me the wrong way. You only get ASI's from whichever class gives you the most. You get all the other class features of both classes, but you gain and advance them all one level slower. The primary balancer, though, shows up in two ways. For each class, you gain either half the effect, or you must wait an additional level (so a total of 2) to get it. Half-effect generally applies to set, numerically quantifiied features, such as +hp for Second Wind. (You'd still roll 1d10 for simplicity, but only gain half the +level value.) They'd also apply to things like Arcane Recovery, number of times you can use Channel Divinity, the weapons an Eldritch Knight can be bonded to (so only 1 instead of 2). And importantly, it applies to spell slots. Everything is rounded up (So so you always get your 1 spell slot when you gain access to a new spell level, for instance). If you are going Fighter/Wizard, Eldritch Knight is the way to go, because you add together the spell slots from each class (then round up the total), which still leaves you with a lot less spell slots than a single classed character. For some features this is manifested by simply not gaining an improved form. A fighter will never get a second use of Action Surge, or a third use of Indomitable. For all the features that don't halve well, you get the normal feature, but it is delayed by an additional level. Note that it isn't actually true that you get
all the features, because you will automatically lose your capstone in both classes due to the one level delay. This is intentional.
While this one has more of a system than the other one, it still effectively requires a write-up for each class to decide which features are halved and which are delayed, because it isn't always completely obvious and some decision making is required.
The write-up of an Eldritch Knight/Conjurer with this system looked more like what I want than any of the others (though I haven't yet compared my sample multiclass against a Valor Bard and a Tempest Cleric, which look like good benchmarks for comparison), but I'm hoping for an official system that is simpler and I will like at least almost as well.
And because I don't want to have the same discussion on two concurrent threads, I'll address a point from my Bladesinger thread about why Bladesinger isn't good enough to model the AD&D fighter/mage. In essence, other than the armor and weapon issues I was discussing there, I think 5e's Bladesinger is a great translation of the original kit, and not a horrible translation of the fighter/mage concept. However, while it is true that it isn't really missing much fightery stuff from the AD&D version, this is no longer AD&D. It needs to have more fightery stuff from the 5e version. Bladesinger is a good class for someone who really wants to go with the 2e kit theme, and doesn't mind being a full wizard and dabbling fighter to do it, just like Eldritch Knight is okay for someone who wants to be a fighter who dabbles in wizardry. (I think Bladesinger is much better conceptual fit personally, because Eldritch Knight is too low on the spellcasting to feel like a fighter/mage, while Bladesinger is a bit better at feeling like one.) So we have two extremes of full classes dabbling in the others, but nothing that gives us a
good balance between them with similar abilities to the originals. I should point out that AD&D (either edition) XP tables would put your fighter/mage at 15th level of each when a single classed mage was 20th level.
I think you're changing the subject here. As a Fighter 10/Wizard 10 you will never have 9th level slots. You'll never even have 6th level slots. 5E's default multiclassing rules are incapable of modeling a high-level fighter/mage.
If you're fine with that omission, then all right, but the answer to [MENTION=20564]Blue[/MENTION]'s question "why are you doing this?" is because 5E's PHB rules don't really support concepts inspired by old-school multiclassing, and yet I think it's possible to do fairly elegantly.
I haven't been able to come up with something that is both elegant and feels right to me (meaning it capture the original feeling but updates it to more modern design sensibilities).
Poll results indicate that many or most people are 100% fine with the status quo, and there's no real danger of that status quo changing because I doubt WotC is ever going to publish their "gestalt" rules in a usable form.
I sure hope they at least give us an UA of them. Ideally they put one of those out, and then use feedback to revise it into a good form for inclusion in the crunch book at the end of the year. I can't think of any good reason for them
not to do that, other than perhaps they are scratching their head over how to do it right just as much as everyone else. But there is a reason we pay them for this stuff, so I hope they can come up with a solution.
Yea, the non-linear increases in power of higher-level class features has always made the 10+10 != 20 problem for multiclassing pretty hard to solve. 3.X tried to patch it with Prestige Classes with only partial success. I think 4e came the closest, between Hybrid Classes and class abilities which were more equivalent between classes at higher power levels.
Yes. While Hybrid multiclassing felt unsatisfying to me (not that I played much 4e anyway), I think with the way post AD&D editions have worked, allowing access to high level abilities from both classes really is something that needs to be included.
IDK if I can accept an optional rule in 2e as establishing "tradition." 1e & 0D&D should have something to say about it, too. Then there was 3e, from which 5e lifted in MCing system.
How about the BECMI elf class?
Some of the combinations seem to get more out of being paired. For example a wizard/fighter gets fighter hps & HD, full armor & weapon proficiencies, can have CON saves which are a big boost, and full casting including spells like Shiedl which synergize well with heavy armor. Oh, and more ASIs, which could be used to boost wizard ability scores or take feats that benefit the wizard side.
On the other hand, a paladin/ranger doesn't get a great deal. HPs are about the same, proficiencies are about the same, both get extra attack, etc. They do have two different casting progressions but both at half speed,and the speed is delayed due to the XP split.
This isn't bad - not all combinations are created even. But it seems to push for characters to take two very different classes and leaving similar classes. Like everyone will be a "full caster/martial type".
Am I needlessly worrying?
As [MENTION=6787650]Hemlock[/MENTION] noted, the traditional combinations didn't allow similar classes to multiclass. 2e codified it a bit further by reference to the class groups (Warrior, Priest, Rogue, Magic-User). In essence, there are certain combinations that are traditionally modeled, and others that just aren't. I'd probably impose those restrictions in my own games, as well as make them racially limited traditions. For instance, dwarves would almost never be paladins. The dwarf equivalent is the dwarf fighter/cleric. Different, but fulfilling a similar role in dwarf society.
A 20th level C10/W10 can only cast 5th level spells but has 9th level spell slots. At equivalent xp to a 20th level character, a C15/W15 2e-multi can cast 8th level spells and has an 8th level spell slot. To me, that's at least somewhat equivalent.
(Just quoting you because it provides a jumping off point for something I wanted to add)
One of the impetuses of this sort of conversion is to allow character to get higher level spells. While there is some utility in scaling up spells into higher level slots, it doesn't capture the aesthetic of the multiclassing concept. For example, in a party of 20th level characters an Eldritch Knight's is just a fighter who dabbles in magic with his 4th level spells--not a fighter/mage. A character who can cast 8th (or even 7th) level spells, is a respectable mage--not on par with a single-classed mage, but at least someone who would hang up his armor, put on a robe and a pointy hat and go sit down at the table with other wizard to discuss arcana and compare spellbooks. And he has a similar relationship to fighters. Obviously inferior, but obviously a bonafide member of the club, not just a dabbler.