Are you adept at using psionic powers? Is your belief in the Deity large enough to channel its energy for healing? Or would you rather just smash everything to pieces with a big club... Magic, stealth, brute force - choose on of the various classes available in Avatar to fit your liking!
These classes are available for everybody when starting a new character: Choose to be a magic user or fighter, a stealthy rogue or an archer ...
Once you reach mortal level 50, just prior to advancing towards becoming a Hero, you may try to pass the requirements to change your class into a prestige class.
It takes the power of a Lord to change into a remort class - forsaking the higher form to start the adventures over with one of these special professions.