the Unbound Sky
All of the Classes of the Core Rules, the Advanced Player’s Guide and the Ultimate Magic and Ultimate Combat books are applicable for play in the Unbound Sky. Actual training and or acceptance as a member of a given class can sometimes be restricted by race or culture, however.
Cleric – only Humans, Demihumans and the Plane-touched can become Clerics. Reasons unknown.
Druid – only characters of the Uplifted races can become Druids. No one is sure exactly why, but there are theories.
Ninja – only the Tengu know the secrets of training Ninja, and they aren’t telling.
Samurai – only the Tengu know the secrets of training Samurai, and they aren’t telling.