At the time of creation, the Mage picks 1 to 4 Magics using a point-buy system, which restricts certain "unbalanced" combinations. All Mages have a max of 4 points.
Unlike normal Mages, these Mages can only be used in RP Story lines/arcs. And are meant to be a sort of challenge to a group of players, usually a main antagonist/rival of sorts. These Mages have a max of 5 points, granting them access to certain magics that allow them to fight a group of mages without getting "floored" in the first 30 seconds of combat. Note that Boss Mages are meant to be a a challenge and thus must be defeated (and in most cases arrested) at some point in the story line/arc.