In D&D 3.0 and related editions, a prestige class is a class that a player can take in addition to their starting class, to expand the options their character has or to specialize in certain aspects of said class.
Introduced in 3rd edition Dungeons and Dragons and part of D&D 3.5e, Pathfinder and the D20 system, prestige classes are mini-classes that the player character can take levels in in order to expand their options: prestige classes exist in a number of different categories:
- Focusing on specific parts of the class and improving them: wizards become better at casting certain schools of magic, rangers get bonuses to their archery, druids can turn into more creatures.
- Becoming able to do things that a class could normally not do, or was not especially good at before: Druids become able to turn into creatures they normally could not, Monks become more capable at grappling enemies, warmages gain access to divine magic used by clerics and so on.
- A mix of two classes: this requires the character to have multi-classed in two different types of characters. By taking levels in a prestige class like this the character becomes able to function as two characters in one, though often these are not as good as "pure" character of equal level who has not taken levels in the other class. These are sometimes called "theurges", after the first class like this, the Mystic Theurge.
- A mini-class: these classes are radically different than the classes the player took levels in in order to qualify. This mostly serves to give the character a flavor, with the initial class serving to support the prestige class. Examples include the Dread Pirate, giving a pirate flavor to a rogue, or the Ur-Priest, a user of divine magic who despises the gods, stealing his magic from them instead of praying for it.
A character can get levels in a prestige class if they qualify for it, from a variety of sources. They cannot take levels in their prestige class the same level they qualify for it: they have to wait until the next level. Things that the player might need to qualify for a prestige class:
- Being able to cast spells: either a specific spell or at a specific level
- Performing some act not specified in the rules: spending time at some specific place, finding a certain area, performing some kind of ritual etc.
- Being in possession of something: a magic item, a mundane item of certain size, a vehicle, a specific amount of gold etc.
- Having died and be brought back.
- Being of a certain race or related to some kind of being by blood.
- Contact with a specific kind of creature or a god.
The downside to taking levels in a prestige class is that doing so the character does not gain the class features of their base class. For some classes this is more problemantic than for others. Some prestige classes grant unique and potent bonuses when they reach their final level, while others give their final bonus to the special feature the prestige class grants.
Prestige classes are frequently used for optimalization purposes, sometimes using as little as one level in their builds.