Multiclassing

Multiclassing is a Dungeons & Dragons rule whereby a character may possess more than one character class. A subtype of this is dual-classing, where a character progresses in exactly two classes at once.

A multiclass character is generally less powerful overall, relative to a single-class character. Nevertheless, rules for it have appeared since early editions of the game.

History

Original D&D

The original Dungeons & Dragons 3-Volume Set (1974) featured the elf, which could switch between fighter and a magic-user at will.

Basic D&D

Multiclassing was not available in the "Basic" D&D product line.

AD&D 1st edition

The Players Handbook (1e) (1978), p.32 introduced the idea that a character may take more than one class.

By these rules, Humans are permitted to have two classes, although once they adopt the second class they are expected to forgo the use of the abilities of their first class or they will gain no XP. They require high ability scores to qualify for the multiclass.

Other races ("demihumans") have more versatility in multiclass combinations, varying by race in terms of which combinations are allowed. Two-class and three-class combinations are possible.

AD&D 2nd edition

Multiclassing works much the same way in the Player's Handbook (2e) (1989), p.44-45. A human only may "dual-class", where at any point after reaching 2nd level they stop advancing in their original class and start from 0 XP advancing as a new class. A demihuman "multi-class" character instead starts as a multiclass character and divides their XP equally between their classes.

D&D 3rd edition

In third edition, multiclassing is handled simply. All characters advance by the same XP threshold regardless of class. When a character levels up, they may advance one level in any of their existing classes, or add a new character class at level 1. A multiclass character has the sum of all their class abilities.

There are no limits by race, and a character does not need to declare their intention to multiclass at level 1.

However, per the Player's Handbook (3.0) (2000), a character suffers a 20% XP penalty for each class which is not within one level of their most experienced class. Each race has a "favored class" which is ignored for the purpose of calculating this penalty. Many DMs ignored this rule.

Prestige classes are a special type of class designed explicitly to be multiclassed into.

D&D 4th edition

Multiclassing was more limited in 4th edition. Per the Player's Handbook (4e) (2008), p.208, Players could take "multiclass feats" to gain skills, powers, or class abilities from another class.

D&D 5th edition

Rules for multiclassing appear in Player's Handbook (5e) (2014), p.163. The rules work similarly to D&D 3rd edition, where a character may stack levels in multiple classes. An additional rule requires characters to meet the prerequisite of certain ability scores, such as Wisdom 13 to multiclass to or from cleric.

There are no XP penalties for uneven multiclassing. One could in theory play a high-level character with only one level in each character class; however, such a character would be underpowered, and would only really created as a joke.