started the game, and worked through to part way into act 1. liking the game but i have no clue on what the MC trainings menu uses for its point system, on any other character its loyalty. but for the MC is mastery. I've tried to find were the description of it is but the help menu only shows the last popped up tutorial and web searching goes no where for me. 

Mastery points are gained by completing certain main quest plot points. I got three by completing the mayoral election. They weren't all given at once. Not sure exactly when they were given

Its currently somewhat bugged with its prices, should be fixed on next update