My OD&D Multiclassing

The other day, I had to end a post about OD&D with the words, "Let a thousand multiclassing rules proliferate..." So here's my own offering:

Adding Classes: To add a new class, a character needs an ability of 16 or more in the new prime requisite, and must sacrifice their current top class level. Elves automatically start with two classes.

Experience: At the start of each adventure, the character specifies which class they are training in, and all XP is awarded to that class. Normal restrictions apply (at most one level per adventure).

Benefits: The multiclassed character uses the best entry for hit dice, attacks, and saves; they can freely use any other abilities (weapons, armor, skills, spells, etc.). Fighter/Wizards may cast spells in leather or chain mail, but not plate; thief skills are restricted to leather armor only.

Monsters: Monsters may use the same rules, treating base hit dice as Fighter levels with 6-sides.

A few comments follow. First, keep in mind that I now use Greyhawk-style Thieves to replace Clerics (albeit with d6 hit dice and skills simply rolled d20 + level + Dex >= 20).

I felt deeply that when adding a class, something had to be sacrificed in exchange for this benefit, and this price had to be fairly precious at any level (hence no fixed XP cost). The result was the "sacrifice their current top class level" clause, which I think is fair. In some sense this is similar in spirit to 3E multiclassing, but much less of a full-system overhaul.

The "specify which class they are training in" at adventure-start for all XP was an attempt to retain the spirit of the "freely switch class... but not during the course of a single game" from the original Elf description of multiclassing.

Using only the highest hit die type may seem odd in retrospect, but I've written before as to how it's elegantly consistent with all the other "max" operators for multiclass abilities in OD&D/AD&D. The implication is that you should keep separate hit point scores for each class, and only use whichever one is currently highest.

Finally, here's the reason for allowing Fighter/Wizards to use leather/chain but not plate: While the OD&D Elf description allows them to "use magic armor", for some mysterious reason, Elves never appear in plate in the original rules. The Vol. 2 monster entry has them all in chainmail. The Swords & Spells entry has the heaviest-armored Elf classification wearing chainmail. (And likewise 1E Bards can cast in chainmail but not heavier types.) So let's say that chain is broadly conducive to spellcasting, but plate is prohibited. It seems both consistent with the source material, and a useful and elegant game-balance restriction.


  1. As far as specifying which class gains XP, you might consider altering it to have the player choose at the time of XP award rather than at the start of the adventure. This is likely mostly a semantic change, being as XP is usually only awarded at the end of the adventure. However, I think it has two advantages:

    First, less book-keeping. When I'm given the XP for the adventure, I don't have to remember which class I said back at the beginning I was going to put it towards. Especially useful if the adventure spans multiple play sessions.

    Second, it allows the player to base the decision on most recent experience. Basically, when the XP comes I can decide that I really could have used some extra spell power in that last adventure so I'm putting the XP towards Magic-User instead of Fighter. Or I could decide that the amount of XP will level me in Fighter but not Magic-User, so it's better applied there.

    OK, in writing that out, I realize there is a slight advantage of choosing at award time in as much as you know the amount of XP before you make the decision. Of course, the DM could just ask the player to choose just before telling the player the number.

    Anyway, my two cents.

  2. Dh, it's a very good point and initially I was thinking exactly the same thing. You're right that it would look like one less thing to remember if we did it at award-time.

    On the other hand, what convinced me to go this way was: (1) OD&D's language that a "switch" can be made only before an adventure, (2) short-circuiting the player analysis/advantage you point out to min-maxing where the XP goes, (3) a bit of realism that what's being trained/practiced is known while the adventure is in play, and (4) the flip-side being that we might likely forget to decide as a play session is wrapping up/out of time, and so it's best to document that when we first sit down so we don't forget.

  3. When I read elf's description, I see:

    Elves can adventure as fighters or magic users.
    Regardless of which they choose, they may always employ weapons, armor and spells. They may not cast spells in non-magic armor.
    When adventuring, he chooses which class he is advancing on the adventure, and uses this class's to-hit values and saving throws. All experience earned is applied to the class chosen, and they can advance Fighting Man as high as level 4 and Magic User as high as level 8.
    In the case of HP, for some reason I'm led to believe that in OD&D *all* dice for hitpoints are rerolled at each level gain. How else could one rationalize an increase from, say, 1+1 dice (one die plus one pip) to 2 dice (two dice). Does the adventurer lose the +1 and roll a die instead, or does he keep it? No, I think the whole sum is rerolled at each level. In such a case, I would rule that a character can keep the greater of either his new roll OR his current total plus 1. Thus, they always gain at least 1 hit point on each level gain.
    What does this mean for elves? Well, in the case of the elf he would get to roll the dice for hitpoints each time either class rises in level in this way. He starts with the fighting man's dice in any case, ignoring the first level of Magic User for simplicity. Thus he'll be rerolling his hit dice 10 more times in his career.

  4. "When adventuring, he chooses which class he is advancing on the adventure, and uses this class's to-hit values and saving throws."

    I basically read the same thing in Vol. 1 alone, but I do feel that it's contradicted by the description in Vol. 2. There's no mention there of having to choose which class is "active" for members of a band of NPC Elves.

    And when I think of the prospect of having to specify that for every NPC Elf we ever encounter, I have serious doubts that that was ever really the intention.

  5. There's truth to that.

    The way I see it, "monster elves" don't play by the rules.