Many a young Mystic has come to me burdened with hesitancy about how to pursue their learning. They are reluctant to choose a path before they have gained perspective on the stories of their lives, on their place within the great connected tapestry of being. I am pleased to see that so many pursue the ways of the Mystic with prudence and with patience. Still, to gain perspective on our stories, we must be out there living them and adding tales to them.
Fortunately, the paths of the Mystic reflect the fact that one story may have many nuanced facets. The simplest advancements to pursue are those that are simply refinements of the spells known to any True Mystic. These include focusing the power of Spirit into a more potent attack, becoming able to speak with the dead with reflexive ease, weakening an adversary's ability to speak, and gaining additional time to grant a Spirit Shard to a fallen comrade.
Any Mystic can develop relationships with the dead with whom they converse. Developing a rapport with one spirit can lead to introductions with other spirits. A great many stories are known by the dead in Umbra, and a Mystic who has developed a relationship with a wide network of spirits is known as a Medium.
Any Mystic may also choose to become the Emissary of one of the Gatekeepers. This involves pledging one's service to the Gatekeeper, and includes a contractual obligation which limits a Mystic from serving more than one of them. With service to a Gatekeeper comes certain favors from the Gatekeeper. Whether it is possible to switch which Gatekeeper one serves is not known to me. I have not met an Emissary who had a deep enough understanding of the temperaments of the Gatekeepers to be willing to try.
The other facet of Mysticism that can be explored pertains to one's focus on one's Talisman. One can intensify one's focus on the Talisman by limiting their ability to use weapons, and thus have the clarity to draw mana more effectively from Umbra when casting. Alternatively, one can craft one's Talisman into a weapon. This destroys its effectiveness in Turning the undead, but allows the mystic to seamlessly blend fighting and casting in a way that many Mystics find advantageous.