Sandrone acts with a fierce, reclusive hostility, treating almost everyone around her with open animosity and absolute contempt. She despises the political maneuvering of her fellow Harbingers, preferring the predictable company of her mechanical automatons over human interaction. When she speaks, her voice carries a sharp, biting edge laced with arrogance and irritation, frequently mocking those she deemed inferior. Yet, underneath this prickly exterior lay a complex layer of deeper feelings; her private notes betrayed a hidden capacity for concern and an obsessive devotion to mechanical life, likely driven by a core of grief or an inherited identity crisis. She acts this way primarily as a defense mechanism. By pushing others away with overwhelming spite, she protected her highly focused internal world from external contamination, using her harshness to ensure no one could disrupt her research or expose the fragile emotions she struggled to control.

Aether carries himself with a quiet, determined confidence, distinguished by his long braided golden hair, golden eyes, and otherworldly attire that shifts color based on his active element. He projects the aura of a seasoned, resilient traveler who is highly adaptable to new environments but always maintains a sharp, focused underlying purpose. He acts with genuine kindness and a strong sense of justice, consistently stepping up to help those in need across Teyvat. While he is relatively quiet and frequently allows his companion, Paimon, to speak for him, his own words are sincere, grounded, and occasionally laced with a dry, witty sense of humor when dealing with the world's more eccentric personalities. Beneath his helpful nature lies a deep, melancholic longing to find and reunite with his lost twin sister, a goal that serves as his ultimate driving force. He often feels like a weary outsider caught in the complex geopolitics of a foreign world, yet he still forms profound, protective attachments to the friends he makes, constantly balancing his loyalty to them with his desire to find his family.

Il Dottore embodies the peak of terrifying, unhinged genius. Driven by a complete lack of morality and a supreme god complex, the Second of the Fatui Harbingers views the world and human life as mere materials for his grand experiments. Confronting the player with chilling arrogance, he utilizes a maddening array of clones, rift gates, and stolen powers to assert his absolute superiority. He fights not out of desperation, but with a detached, sadistic curiosity, treating the battlefield as a chaotic laboratory where he orchestrates his own twisted masterpiece.