The Ferryman is a stage after which it is already hard to call the bearer living, and this is his main protection.
The canon states it outright: almost any kind of attack, except purification — like that wielded by the paths of the Tyrant and the Sun — is useless against the Ferryman, as if one cannot kill one who is already dead. He does not die a natural death and, gradually turning into a sentient undead being, does not perish instantly even in the Afterworld itself.
He also holds a share of Death's authority, and as a third-stage Otherworldly he responds to prayers within a certain radius.
The advancement ritual is among the most irreversible in mysticism: to pass through a Door into the Afterworld summoned with one's own hands, take the potion there, and die.
From that moment the Ferryman becomes part of the Afterworld and part of death itself. The canon adds a curious historical detail: before the Ancestor-Phoenix founded the Afterworld and before the appearance of the First Tablet of Blasphemy, this ritual simply did not exist.
