Howdy, folks!
This is an attempt to adapt 2e-style multiclassing for 5th edition, for those who like it. Actually this is more of a "do you guys think it would work?" post than anything else. So really, just an idea to be discussed here.
So what is 2e multiclassing (in case you don't know)?
Basically, you have 2 classes (maybe 3) and you split all XP you gain evenly between your classes. So if you are a FIghter-Cleric, and you gain 2000xp, 1000xp goes to the Fighter class and 1000xp goes to the Cleric class. You always evolve all your classes together instead of "picking" a class choice each level. You also gain the full benefit of each class you have at the level of that class. So if you are a Fighter/Cleric you gain the To Hit of a fighter, HP of a fighter, spells of a cleric, the best of each save, etc.
First let's have a look at the table below:
This is a comparison between XP progression in 2e and 5e. Actually, each class in 2e had a different XP progression, but since this progression is normalized for everyone in 5e, I picked the Fighter 2e progression only as it seemed to be the "average" one.
What do the colors mean?
That if you are multiclassing and have 2 classes, by the time you have, for example, 4000xp (dark green color), you would be at level 2, while a single-class character would be at level 3 (where the dark green is in the single-class column). The same goes for all colors. This shows how many levels "behind" a multiclassed character is.
So how did I come up with the 5e multiclass table on the right side?
Simple. The first column in the 5e table is the normal XP in 5e for a single-class character. I just copied the "colors" and thus the level difference from the 2e table. And then filled the respective cells with the equivalent 5e XP from single-class. This way, if a multiclass character were 2 levels "behind" at level 10 in 2e, he will be the exact same in 5e.
TL,DR so how would 2e-style multiclassing in 5e work, as far as XP goes?
Very simple, you pick the 2 classes you want, and you use the 5th Edition "2 classes" table on the far right for character progression, instead of the regular 5e progression. This is now the XP you need to level up. And each time you level up you gain the benefits from both classes leveling up.
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Now let's get to the actual multiclassing:
Hit Points and Hit Dice: use the best HD out of the two classes.
Armor and Weapon Proficiencies: you gain from both classes.
Tools: you gain from both classes.
Skills: pick the highest amount any of your classes give (ex: if fighter-rogue, you have 4 skills since rogue gives you 4). You can choose your skills from any of your classes' skill list.
Saves: you gain proficiency with saves from both classes. If two classes grant the same save, they don't stack or double, you just gain the normal proficiency for it.
Ability Increases / Feats: if at a certain level you would gain ability increases from both classes, you don't get them twice, only the normal +2 ability as if you were single-class (this will likely happen at standard levels: 4, 8, 12, 16 and 19). When you gain an ability increase from just one class at a different level, this means it's not "standard" and thus a class feature, so you do get this extra increase.
Class Abilities: you get all class features from both classes, with the exception of Ability Increases which are covered in the paragraph above.
Spellcasting: you gain the full benefit from spellcasting and use the normal rules for it. If both your classes can cast spells, treat each spell progression and memorization independently. So if you are a Wizard/Cleric: prepare Level+Int wizard spells and Level+Wis cleric spells. Cast each spell using the corresponding spell progression for each class.
[Variant Spellcasting]: the above rule treats spellcasting about the same way as 2e did it with multiclassing, so I left it as "default". But if you find that's not to your taste tracking 2 separate spellcastings at a time, you can use this rule: Add up the amount of spells/day from both classes into one pool, and you can cast spells from both classes using any spell slot. However, you can only prepare Level + (your best casting modifier) spells, which can be from any or both classes.
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So that's it.
This guide only covers having 2 classes. But it would just be a matter of making the XP table for 3 classes as well.
Now the question is: what do you guys think? Do you think this could work? Will the level difference between multi and single class characters balance itself well enough, or will one or the other clearly be more powerful?
Also, any thoughts or remarks on anything that I might have forgotten?
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EDIT
Unbalance Concerns Section (combos)
I'll open this section here for any comments you guys make about possible unforeseen "combos" that may become overpower. Whatever lies under this section may or may not be overpowered so I'll leave it up to each of you to decide whether to allow it or not, and maybe offer some possible solutions.
Fallingcicle wrote:
- A rogue's full sneak attack + the fighter's extra attacks would be... ouch. Even with the 1/turn limit for sneak attack, a fighter/rogue will still be doing way more damage than a single class fighter or rogue.
- If you're curious about why "use the best HD" and not "use the average HD" as it was in 2e, check out this reply for a table and explanation:
http://community.wizards.com/comment/50839521#comment-50839521
Looks fine. I hate 2E style multi-classing, but I see absolutely no reason not to include it as a module. If they haven't started work on one, the devs should take a look at this thread for as starting point.
I am concerned about the XP table after level 7 [23,000 XP]. In ADnD, you had a similiar thing happen with MCing, but generally speaking the huge level delta between single-classed and multiclassed didn't happen until after name level (and most campaigns ended before then and those that didn't took an entirely different tenure, and even the game itself shifted after name level...just look the hit-dice progression for one). However, in 5e expect (just as with 3e and 4e) to have most campaigns last at least well into the teens....and by level 20 (single classed) the loss of six hit-dice is just overwhelming especially considering you don't get everything from both classes (notably feats/attribute gains).
Just my two coppers.
-Polaris
Rastapopoulos wrote:
Thank you Rast. You are a rare treasure on these boards.
I love this system and will likely just drop it into my 5e game if I end up playing it. I was planning on doing exactly what you did but you did it! So now I don't have to do it.
I never liked 3e multiclassing. The idea that you could just start a new class whenever is kind of crazy to me. I was going to just ban multiclassing but this approach is a good one. If you want to dip then take some feats instead.
This seems a lot like what 3/3.5e called Gestalt characters, though with an altered XP progression to offset the bonuses of progressing both classes at once. I think the characters would be very strong, but am not sure if the XP offset would be enough to balance it out in game. It might though.
How would taking a second class work at later levels with this system?
Emerikol. wrote:
In 2e multiclassing you rolled both hit dice and divided the result by two, giving you the average of the HP between the two classes.
Gazra wrote:
Your character is going to be missing 6 HD worth of HPs. Multiclassing worked in AD&D because after level 10, you gained very little HPs. I think you'll lose too many HP with this.
Why don't you try something almost equivalent:
HPs: Use the average die (rounded up)
HD: Use the average die (rounded up)
Class Features/Spells: as a character of 2/3 your level (rounded up)
For example, if you are a level 17 fighter/wizard, you would have 17d8 HPs, 17d8 HD, the class features of a level 12 fighter and the class features of a level 12 wizard.
Gazra wrote:
@OP: I don't agree with you on a lot of things, but I do love 2e-style multiclassing so you definitely get a 
for your effort here.
I have given some limited thought to how I would implement 2e-style multiclassing in DDN, and I think that it can largely be done exactly as it was in 2e even if one isn't using Xp for advancement. One of the sticking points for me though is encounter design. I know some people don't care about having Xp budgets, but I do. So, for people like myself who like 2e-style multiclassing and Xp budgets for encounters, I was thinking that a 2e-style MC'd character could count as 1.5 characters for the purpose of determining the Xp budget (the character has more abilities but doesn't get more actions to use them all so she shouldn't count as two full characters).
Rastapopoulos wrote:
Sailing_Pirate_Ryan wrote:
mellored wrote:
A few ideas Rast.
Seems tyopu have roughly tripled the xp requirement. Perhaps doubling it would be more than enough and since the exp requirements are harsh you could just let them use the best hit dice. New clones are using an average of both the diceand they add the xp table togather so a Swordmage (fighter/wiz) would hit level 2 at 4500 xp and have a d6 or d8 hit dice depending on the clone. You could just use the Myth and Magic guidelines for that I suppose.
Another way of doing it is using some sort of level adjustment a'la 3rd ed. Basically if you want 2 classes you are do level behind so you could have a 3rd level fighter/wizard or a 5th level single class character. Maybe 3 levels behind if you wanted 3 classes.
I ran this idea past my players back with the gestalt rules in 3.5 UA book, The idea was to run gestalt characters along side normal PCs. I asked them how many levels they would give up to have 2 classes with the best HD/saves etc of each class.
1 level behind: Everyone more or less indicated they would gestalt over a single class.
2 Levels behind becomes a maybe
3 levels behind became a hell no
a Fighter/Wiz in 5E would have a d8 hit dice (average) or d10 if they get the best of both classes.
D&DN has flatter math but I suspect 2-3 levels behind is the magic number or something like double the xp for 2 classes and triple the xp for 3 classes as your level 14 double classed character is close in levels for an AD&D triple classed character anyway.
Seems like many of you are worried with HP loss due to having less levels, so I did some calculations comparing 2e and 5e and realised that using best HD out of the 2 classes in 5th edition actually gets you closer to 2e multiclass HP than using average like in 2e.
Let's have a look at this table below:
The first 2 tables compare the HP of a Fighter-Cleric multiclass, first in 2nd edition and then in 5th edition.
The 2 tables below compare a Fighter-Rogue 2e multiclass with a Fighter-Wizard 5e multiclass. (Why? Because both have d6 HD. Since no class uses d4 in 5th edition it would be sort of a pointless comparation.)
For 5th edition HP I used the "fixed" HP per level option in the book, as well as maximum HP at 1st level.
For the 5th edition multiclassing I used "pick the best Hit Die of your two classes", for 2nd edition I used the default of average dice.
The last column shows the % of your level 14 multiclass compared to the Level 20 equivalent Fighter (the one who has the highest HP). So a level 14 fighter-rogue with +1 Con in 2e would have around 69% of the HP of a level 20 fighter. In 5e he would have around 70%.
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TL,DR: As you can see, using "best HD out of your two classes" in 5th edition leaves multiclass HP very close to what it was in 2e with average from two classes (in terms of % of HP).
The % were a bit more swingy in 2e depending on your Con Modifier, but not that much, and it was very rare to have more than +2 on Con back in 2e since you needed 16 Con for that and overall ability scores were much lower in 2e than in 5e.
If you think that having around ~70% of the HP of a single-class fighter is still too much of a HP loss to be worth the multiclassing, you can play around with values a bit, but since it's more or less what it was back in 2e, I'll leave it at that since this is the goal of this post. 
I'm gonna edit back the original post to "use the best HD" then.
@Rasta: how does the proficiency bonus work? do you get the proficiency bonus of a level 14 character?
Gnarl wrote:
ankiyavon wrote:
This is really great! I really like the chart!
As others have said, my only complaint is that it doesn't follow the 2e rule for hit points.
"The character's hit points are the average of all his Hit Dice rolls. When the character is first created, the player rolls hit points for each class separately, totals them up, then divides by the number of dice rolled (round fractions down). Any Constitution bonus is then added to the character's hit points. If one of the character's classes is fighter and he has a Constitution of 17 or 18, then he gains the +3 or +4 Constitution bonus available only to warriors (instead of the +2 maximum available to the other character classes)."
ankiyavon wrote:
Emerikol. wrote:
Here are a few more rules I found from 2e. You might want to restrict the use of armor for multi-class wizards. That would bring back the need for elven chain.
Multi-class characters can combine abilities from their different classes with the following restrictions:
Warrior: A multi-classed warrior can use all of his abilities without restriction. The warrior abilities form the base for other character classes.
Priest: Regardless of his other classes, a multi-classed priest must abide by the weapon restrictions of his mythos. Thus, a fighter/cleric can use only bludgeoning weapons (but he uses the warrior combat value). He retains all his normal priest abilities.
Wizard: A multi-classed wizard can freely combine the powers of the wizard with any other class allowed, although the wearing of armor is restricted. Elves wearing elven chain can cast spells in armor, as magic is part of the nature of elves. However, elven chain is extremely rare and can never be purchased. It must be given, found, or won.
Thief: A multi-classed thief cannot use any thieving abilities other than open locks or detect noise if he is wearing armor that is normally not allowed to thieves. He must remove his gauntlets to open locks and his helmet to detect noise.
Good work, Rast! I'm still considering making custom subclasses to cover 2e-style multiclassing (though getting a subclass at 3rd level may have bolloxed that idea), but I'll take a look at how this works in practise.
I could see it being a fun option for players and DMs with a high level of rules mastery. And adding more fun modules in the DMG is always a good idea.
Question: How are you going to deal with the Linear Warrior/Quadratic Wizard issue? More specifically, non-casters are most powerful at low levels, when there superior armor/hit points/weapons/proficiencies and signiture class abilities are most effective. So stacking those abilities on top of each other is going to lead to very powerful low level builds. But spellcasters are most effective at level 7ish or higher, and they're basically playing an entirely different game at high levels. So splitting up their spellcaster progression and spell improving abilities is going to lead to much weaker builds.
So for example, a Fighter 2/Rogue 2 (with Fighting Style, Action Surge, Second Wind, +1d6 Sneak Attack, Expertise, Thieve's Cant, Cunning Action, and proficiency with basically everything important) is probably going to be a lot more powerful and useful then a Fighter 5. On the flip side, a Cleric 14/Wizard 14 (7th level spells) is going to have a hard time keeping up with a Wizard 20 (9th level spells and all the capstone-ish abilities). Or if you pour all of their spells into the same bucket (Cleric 14/Wizard 14 with 9th level spells) they end up radically MORE powerful then the Wizard 20.
TLDR: I think it's a great fun idea, but it introduces all sorts of balance concerns that may be hard for DMs and players to reasonably sort out.
Rast you have Myth and Magic right? How do you feel about the way they handled MC characters in that retroclone in terms of hit points?
Zardnaar wrote:
SteeleButterfly wrote:
Rastapopoulos wrote:
MechaPilot wrote:
Zardnaar wrote:
@Rast:
Regarding level I would just require 50% more xp for MC characters at each level. MC characters can't really use all of their abilities because they are still limited by the action economy. In any given round an MC character almost has to choose what class they will act as. Sure, they have more profs and more options to choose from but they also have less HPs and are less able to focus on a single stat to achieve excellence in their classes.
Regarding 2e-style HPs: I did mean the averaging the die rolls, or more accurately averaging the better of the die rolls or the static values (even in 2e and 3e I always let players use the better of their roll or half their maximum possible roll).
Rather than splitting the hit points, average the hit dice rounding down.
Fighter/anything d8
Cleric/Rogue MC with wizard gets a d6.
Don't bring back the 2e armor rules! No! That ruined multiclassing.
I think the limited proficiency more than makes up for the armor gain.
mellored wrote:
I've been working on a balanced approach to Multi-Classing in both 2nd & 3rd Edition D&Ds.
The concept is called Half-Classes, in 3rd edition D&D it's rather easy to implement and doesn't break the game balance.
What you do is halve everything for each class (this means everything) feats, saves, BAB, spells/day, spell schools, etc...
Half-Fighter/Half-Sorcerer
Ability Requirement: Strength 10 & Charisma 10
Prime Requisite: Strength & Charisma
Allowed Races: Any
Alignment: Any
Hit Dice: (1d7) so 1d8 on even levels & 1d6 for odd levels
Base Attack Bonus: Average
Base Save Bonuses: Reflex (Poor), Fortitude & Will are averaged between Good & Poor
Class Skills: Craft & pick 3 of the following: Climb, Handle Animal, Intimidate, Jump,
Profession, Ride, & Swim. and pick 3 of the following: Bluff, Concentration, Craft,
Knowledge (arcana), Profession, & Spellcraft
Skill Points / Level: (2 + Int modifier) (x4 for 1st level)
Class Feats: Simple Weapons, Light Armour, Shield, & Summon Familiar
Bonus Feats: At levels: 1st, 4th, 8th, 12th, 16th, & 20th
Starting Gold: (3d4 +1d6) x 10 gp
Spell Selection: 1/2 of Spells Known on page 54 PHB (rounded up)
Spells per Day: 1/2 for each spell level as listed on page 52 of PHB (rounded down)
Receives bonus spells per Day for high Charisma as normal.
As you can see the Fighter half looses Martial weapons & Medium Armor feats, but these can always be bought with class feats & bonus feats later on.
The Sorcerer is a easier to handle than a wizard as all you do is cast half as many spells; you keep the same casting level as a full class Sorcerer and you still get high level spells but cant cast as many.
With a Wizard instead of Sorcerer, your school access would be half and spells/day for each spell level would be half, and casting level is full level.
Alternatively if you wanted a more 2nd Edition D&D feel you could opt to allow the wizard cast all spells from all schools, but at the cost of reduced spell progression which would look somthing similar to the bard spell progression table and use 2/3 of your character level as the casting level.
I've got lots of tables & half-class blends already designed for my 2nd & 3rd Edition campains.
True Multi-classing AD&D 3.5 (Solution)
Half-classes:
Half-classes are designed with just the core skills and abilities of that particular class (in other words “half”), so that TRUE multi-classing can happen in the AD&D 3.5 rules (it was broken for magic classes and abused for non-magic classes). After analyzing the different multi-classing systems between the AD&D editions, the DMG 3.0 Multi-class 1st level characters, and the Unearthed Arcana 3.5 generic classes, I've now developed a viable solution that makes multi-classing a lot more fair. Two half-classes can now be paired as a single class which wouldn't require a major overhaul of the AD&D 3.x rules (level advancement is based solely on character level not class level). Each half-class is designed with 50% of full class potential using just core skills, this makes the character skilled in both skill-sets, but not a expert in either one, which is what multi-classing should of been all along.
The half-classes information below are already halved & adjusted, so all you need to do is just add the two halves together to make a full class. A Half-Warrior/Half-Sorcerer gets: Hit Dice of 1d7 (1d8 on odd levels and 1d6 on even levels), an average base attack bonus, an average of fortitude & will saves (min of 1 at level 1 and max 9 at level 20), craft + 3 warrior skills + 3 sorcerer skills with 2 + Int modifier points to distribute among the 7 skills, simple weapons + light armour + shield (but these can be easily upgraded with bonus feats), and (3d4 + 1d6) x 10 starting gold. Weapons, armour, & shield feats stack, so a Half-Warrior/Half-Cleric would get Martial weapons, Medium Armour, and any shield.
Half-Warrior
Ability Requirement: Strength 10
Prime Requisite: Strength
Allowed Races: Any
Alignment: Any
Hit Dice: (1d10)/2
Base Attack Bonus: Good/2
Base Save Bonuses: Good/2 (fortitude) & Poor/2
Class Skills: Craft & 3 of the following: Climb, Handle Animal, Intimidate, Jump,
Profession, Ride, & Swim.
Skill Points / Level: (2 + Int modifier)/2 (x4 for 1st level)
Class Feats: 1 in Weapons, 1 in Armour, and 1 in Shield
Bonus Feats: At levels: 1st, 4th, 8th, 12th, 16th, & 20th
Starting Gold: 3d4 x 10 gp
Half-Expert
Ability Requirement: Dexterity 10
Prime Requisite: Dexterity
Allowed Races: Any
Alignment: Any
Hit Dice: (1d6)/2
Base Attack Bonus: Average/2
Base Save Bonuses: Good/2 (reflex) & Poor/2
Class Skills: Profession & 14 of any of the skills.
Skill Points / Level: (8 + Int modifier)/2 (x4 for 1st level)
Class Feats: 1 in Weapons
Bonus Feats: At levels: 1st, 3rd, 7th, 11th, 15th, & 19th
Starting Gold: (1d4 + 1d6) x 10 gp
Half-Cleric
Ability Requirement: Wisdom 10
Prime Requisite: Wisdom
Allowed Races: Any
Alignment: Any (compatible with Deity’s)
Hit Dice: (1d8)/2
Base Attack Bonus: Average/2
Base Save Bonuses: Good/2 (fortitude & will) & Poor/2
Class Skills: Knowledge (Religion) & 5 of the following: Concentration, Craft,
Diplomacy, Heal, Knowledge (any, taken separately), Profession,
Spellcraft or Domain specific (see PHB page 31).
Skill Points / Level: (2 + Int modifier)/2 (x4 for 1st level)
Class Feats: 1 in Weapons, 1 in Armour, 1 in Shield, & Turn or Rebuke Undead at 1st
Spell Selection: Cleric and only 1 domain.
Spells per Day: 1/2 for each spell level as listed on page 31 of PHB (rounded down)
Receives bonus spells per Day for high Wisdom as normal.
Starting Gold: (1d4 + 1d6) x 10 gp
Half-Sorcerer
Ability Requirement: Charisma 10
Prime Requisite: Charisma
Allowed Races: Any (with a dragon for a ancestor)
Alignment: Any
Hit Dice: (1d4)/2
Base Attack Bonus: Poor/2
Base Save Bonuses: Good/2 (will) & Poor/2
Class Skills: 3 of the following: Bluff, Concentration, Craft,
Knowledge (arcana), Profession, & Spellcraft
Skill Points / Level: (2 + Int modifier)/2 (x4 for 1st level)
Class Feats: Summon Familiar
Spell Selection: 1/2 of Spells Known on page 54 PHB (rounded up)
Spells per Day: 1/2 for each spell level as listed on page 52 of PHB (rounded down)
Receives bonus spells per Day for high Charisma as normal.
Starting Gold: 1d6 x 10 gp
Half-Wizard
Ability Requirement: Intelligence 10
Prime Requisite: Intelligence
Allowed Races: Any
Alignment: Any
Hit Dice: (1d4)/2
Base Attack Bonus: Poor/2
Base Save Bonuses: Good/2 (will) & Poor/2
Class Skills: Knowledge (arcana) and 5 of the following: Concentration, Craft,
Decipher Script, Knowledge (any, taken separately), Profession, &
Spellcraft
Skill Points / Level: (2 + Int modifier)/2 (x4 for 1st level)
Class Feats: Summon Familiar, Scribe Scroll
Spell Selection: Universal & 4 of the 8 schools of arcane magic on page 57 of PHB.
Spells per Day: 1/2 for each spell level as listed on page 55 of PHB (rounded down)
Receives bonus spells per Day for high Intelligence as normal.
Starting Gold: 1d6 x 10 gp
Three way multi-classing is too waterred down for my liking, but some players want it anyways, so here's the following:
Third-Warrior
Ability Requirement: Strength 10
Prime Requisite: Strength
Allowed Races: Any
Alignment: Any
Hit Dice: (1d10)/3
Base Attack Bonus: Good/3
Base Save Bonuses: Good/3 (fortitude) & Poor/3
Class Skills: Craft & 2 of the following: Climb, Handle Animal, Intimidate, Jump,
Profession, Ride, & Swim.
Skill Points / Level: (2 + Int modifier)/3 (x4 for 1st level)
Class Feats: 1 in Weapons & 1 in Armour/Shield
Bonus Feats: At levels: 1st, 6th, 12th, & 18th
Starting Gold: 2d4 x 10 gp
Third-Expert
Ability Requirement: Dexterity 10
Prime Requisite: Dexterity
Allowed Races: Any
Alignment: Any
Hit Dice: (1d6)/3
Base Attack Bonus: Average/3
Base Save Bonuses: Good/3 (reflex) & Poor/3
Class Skills: Profession & 9 of any of the skills.
Skill Points / Level: (8 + Int modifier)/3 (x4 for 1st level)
Class Feats: 1 in Weapons
Bonus Feats: At levels: 1st, 5rd, 11th, & 17th
Starting Gold: (1d6) x 10 gp
Third-Cleric
Ability Requirement: Wisdom 10
Prime Requisite: Wisdom
Allowed Races: Any
Alignment: Any (compatible with Deity’s)
Hit Dice: (1d8)/3
Base Attack Bonus: Average/3
Base Save Bonuses: Good/3 (fortitude & will) & Poor/3
Class Skills: Knowledge (Religion) & 3 of the following: Concentration, Craft,
Diplomacy, Heal, Knowledge (any, taken separately), Profession,
& Spellcraft.
Skill Points / Level: (2 + Int modifier)/3 (x4 for 1st level)
Class Feats: 1 in Weapons, 1 in Armour/Shield, & Turn or Rebuke Undead at 3rd
(-2 levels for effectiveness after 3rd level)
Spell Selection: Cleric only (the Cleric is too basic at 1/3 to have any access to domains).
Spells per Day: 1/3 for each spell level as listed on page 31 of PHB (rounded down)
Receives bonus spells per Day for high Wisdom as normal.
Starting Gold: (1d6) x 10 gp
Third-Sorcerer
Ability Requirement: Charisma 10
Prime Requisite: Charisma
Allowed Races: Any (with a dragon for a ancestor)
Alignment: Any
Hit Dice: (1d4)/3
Base Attack Bonus: Poor/3
Base Save Bonuses: Good/3 (will) & Poor/3
Class Skills: 2 of the following: Bluff, Concentration, Craft,
Knowledge (arcana), Profession, & Spellcraft
Skill Points / Level: (2 + Int modifier)/3 (x4 for 1st level)
Class Feats: Summon Familiar
Spell Selection: 1/3 of Spells Known on page 54 PHB (rounded up)
Spells per Day: 1/3 for each spell level as listed on page 52 of PHB (rounded down)
Receives bonus spells per Day for high Charisma as normal.
Starting Gold: 1d4 x 10 gp
Third-Wizard
Ability Requirement: Intelligence 10
Prime Requisite: Intelligence
Allowed Races: Any
Alignment: Any
Hit Dice: (1d4)/3
Base Attack Bonus: Poor/3
Base Save Bonuses: Good/3 (will) & Poor/3
Class Skills: Knowledge (arcana) and 3 of the following: Concentration, Craft,
Decipher Script, Knowledge (any, taken separately), Profession, &
Spellcraft
Skill Points / Level: (2 + Int modifier)/3 (x4 for 1st level)
Class Feats: Summon Familiar, Scribe Scroll
Spell Selection: Universal & 3 of the 8 schools of arcane magic on page 57 of PHB.
(one of the schools is minor access to a max spell level of 6th)
Spells per Day: 1/3 for each spell level as listed on page 55 of PHB (rounded down)
Receives bonus spells per Day for high Intelligence as normal.
Starting Gold: 1d4 x 10 gp
You know, I've spent most of the last fifteen years trying to "fix" 3.X multiclassing and I was disappointed-- hell, angry-- that they returned to it in 5e.
But you know, the more I play with the new rules, the less I think AD&D style multiclassing is needed. Really, all the multiclassing rules need are some patches. 3.X did it with Prestige Classes, and that was terrible-- but you could take some inspiration from 4e's multiclassing feats and, combined with the 3.X-style multiclassing in 5e, come out with something pretty neat.
edit: I'm already house-ruling ability boosts and feats anyway. But my idea is that it costs a feat to multiclass-- either in advance, or you pre-allocate your next feat-- and then you use other feats to improve your class features. Haven't got the rules worked out real well yet, but one idea is a feat that works like Bard's Magical Secrets ability, but only for classes you already have levels in, and it bypasses your class level limit. So yeah, you can dip Cleric to cherry-pick the spell list, as long as you invest in Wisdom, spend a feat to multi-class, and then spend another feat for a couple of spells. Maybe limit it to spells of no higher than your class level, to make sure you're losing Wizard spells for your Cleric cheese.
2nd edit: And now, for the first time since 3e launched, I am happy with the multiclassing rules I'm using.
You need a feat to multiclass. Ritual Caster and Magic Initiate both allow characters to take levels in the chosen class, Martial Adept allows characters to multiclass as Fighter, and I've created feats that allow characters to multiclass as Monks, Rogues, and Barbarians.
I've also ginned up a couple of multiclassing feats. One that improves on Martial Adept, a conversion of Practiced Spellcaster, and a feat that allows you to learn two spells of levels you can cast from any class list you have levels in. (Maximum spell level is equal to class level in the class.) Probably going to come up with a few more before I'm done, but I can't think of anything right now that's even remotely necessary.
Yeah, I would like to see more abilities like Thief's expertist lost during a Multi class. Certain abilities should be reserved for the single class character.