Each class is granted two options for their master level path. Below is a table detailing what options are available to the current classes.
How to Respec your Master Level Path using a Star of Destiny
If you change your mind and wish to try the other Master Level option, you can do so by using a Star of Destiny. Each master level has ten encounters. The creature your kill during the final encounter, number 10, has a chance to drop one or many Star of Destiny(s).
You use the Star of Destiny while standing next to the Tablet of Destiny in the Hall of Heroes, where the arbiter is located. You will retain all master levels that you have earned to that point.