Deep scions began life as people who were stolen from shore or saved from sinking ships and offered a terrible bargain by an undersea power: surrender, body and soul, or drown. Those who submit are subjected to an ancient ritual widespread among evil aquatic creatures. Its methods are painful and the result never certain, but when it works, the magic transforms an air-breathing person into a shapeshifter that can take on an aquatic form.
A deep scion emerges from the depths in service to their underwater master, which is likely a kraken or some other ancient being of the deep. While wearing the mind and body of the person they once were as a sort of mask, the creature is bent on fulfilling their master’s desires. Sometimes a deep scion returns to their former home—unexpectedly found alive when all hope was lost. At other times the deep scion takes on a new identity. In any case, it is the deep scion’s duty to infiltrate the air-breathing world and report back to their master. When set to this task, a deep scion worms their way into the life of an unsuspecting enemy as a new friend, a lover, the perfect candidate for a job, or some other role that enables the minion to carry out their master’s commands.
The training to which a deep scion is subjected rids it of empathy for those they spy on. Though a deep scion might behave as though infatuated, laugh at the joke of a friend, or appear incensed at some injustice, each of these acts is artificial to the deep scion, a means to an end. The creature believes that their true form is the shape they take when they return to the sea they think of as home. Ironically, however, a deep scion that is killed when in their piscine form is stripped of the magic that enabled them to transform, leaving behind the corpse of the person the deep scion once was.