Progress Levels 0-2 cover the period from the Stone Age to the Middle Ages.
Assassin - Barbarian - Bard - Cleric - Druid - Fighter - Mage - Paladin - Ranger - Thief
The invention of powder and muskets make ancient fighters obsolete (new class: musketeer).
Assassin - Bard - Cleric - Daredevil - Mage - Musketeer - Ranger - Thief
Magic and superstition have disappeared but psionics is discovered (new classes: glamourist, psion). Also, reliable firearms become common (new classes: bounty hunter, gunslinger).
Bounty Hunter - Cleric - Daredevil - Glamourist - Gunslinger - Psion - Thief - Urban Ranger
Computer technology rules supreme (new class: hacker).
Bounty Hunter - Cleric - Daredevil - Glamourist - Hacker - Psion - Soldier - Thief - Urban Ranger
Humanity climbs to the stars and new philosophies allow the mastery of Vril (new class: Vril knight).
Bounty Hunter - Cleric - Daredevil - Glamourist - Hacker - Psion - Soldier - Thief - Urban Ranger- Vril Knight
Anti-Paladin - Blackguard - Knight - Monk - Ninja - Psion - Psychic Warrior - Soulknife
Multiclasses follow rules different from the SRD. The experience is divided between the classes and they level separately, with one level loss, e.g. when a fighter has enough experience to be level 9, a fighter-thief is level 6-6.
HP per level: average of every class
BAB: highest of all classes
saves: highest of all classes
class skills: class skills of every class
skill points: average of every class
spell points: highest of all classes
They can only put a maximum of 3 points per skill.
Fighter-Cleric - Fighter-Thief - Fighter-Mage - Cleric-Thief - Cleric-Mage - Mage-Thief - Fighter-Bard - Bard-Mage - Fighter-Druid - Ranger-Thief - Fighter-Cleric-Mage - Fighter-Mage-Thief