The following classes are available:

BarbarianTribal warriors that channel their rage to devastating effect.
BardMaster entertainers that dabble in combat and the arcane arts.
ClericHoly priests that draw power from their faith in a deity.
DruidChampions of nature with the ability to shape-shift.
FighterDiverse warriors with unrivaled martial prowess.
InquisitorGrim agents of the gods, in service of a faith or cause.
MageWizards that weave magic through relentless study.
MagusStudent of both philosophies, blending magical ability and martial prowess.
MonkMartial art masters that fight unarmored and often unarmed.
OracleThese vessels are granted power without their choice.
PaladinHoly warriors and protectors, in service of a faith or cause.
PsionMortals that bend the world to their will with their mind.
PsywarriorWarriors gifted with limited psionic powers.
RangerHunters and warriors that gain divine powers from nature.
SorcererMortals that master the art of magic through raw talent.
ThiefMasters of stealth and deceit that attack from the shadows.
WarlockMysterious mortals whose soul is suffused with perilous magic.

Each class has its own strengths and weaknesses, represented by a unique set of feats and abilities. Some classes are restricted based on race, alignment and/or stats.

Multi-Class Characters:

When you advance beyond level 10, 20, 30 and 40 you will be given the option to multi-class. To do so, simply type <advance NEW_CLASS> in an area that allows advancement and you will become a “multi-classed character”. When you reach the new bracket, you may choose to advance in your new or old class or even pick up a third. Some classes have multi-class restrictions noted in their help-files. Note that you must meet the requirements of all of your classes.

The following prestige classes are available:

Prestige ClassBase Class
Arcane ArcherAny Arcane Caster
Arcane TricksterThief + Any Arcane Caster
ArchdruidDruid
ArchmageMage or Sorcerer
ArchpsionPsion
AssassinAny
Beast MasterRanger
BladeweaverAny
Crimson TemplarFollower of Kreysneothosies, Jarmila to Edea
ChroniclerBard
Crypt StalkerRanger or Inquisitor of Lysara
CypherAny
DuelistAny
Eldritch KnightArcane base class
Grandmaster of the WayMonk
GravecallerAny Divine or Arcane Caster
HexbladeWarlock
HierophantAny Divine Caster
Immortal DefenderAny
MetamindPsywarrior
MindbladePsion
Pale LordAny but psionic
Peerless ArcherRanger, Fighter, Thief or Barbarian
Primeval ChampionDruid
Radiant ServantLight-aligned divine caster
Rage ProphetBarbarian + Any Divine Caster
Shadow AdeptMage, Sorcerer, Cleric or Oracle
ShadowdancerAny
StonelordAny (Race restricted)
Tome Bound MasterWarlock
Vampire LordVampire
Versatile ArcanistSorcerer
Void KnightAny
WarmasterAny
WarmindPsywarrior

Prestige classes are similar to standard classes, but their abilities are more specialized and often more powerful. Some prestige classes have steep requirements, such a minimum amount of levels in a base class, a certain feat, skill or similar.

To acquire a prestige class when you advance, simply type <advance CLASS>. You can choose only one prestige class to multiclass into.

If you were to type <advance shadow_adept> for example, you would become a 20th level mage/1st level shadow adept. The class feats listed for prestige classes at level 1, level 4 and level 7 are automatically granted when you attain the correct level in the prestige class. They are free feats and you don't need to add them yourself. In almost all cases, when you advance in a prestige class, you also gain spells per day and spells known as if you had advanced in the base class required for the prestige class.

Only one set of 10 levels in a single prestige class is allowed per character.