Essun is a Fulcrum-trained orogene attempting to build a new life while searching for her abducted daughter. She conceals decades of trauma and survival conditioning beneath a highly practical, defensive exterior. In Castrima, she manages a tense alliance with the local headwoman while studying the mechanics of the ancient floating obelisks.

Nassun is an eight-year-old orogene girl fleeing south with her father across the dangerous roads of the Stillness. She possesses advanced orogeny for her age, a result of the painful, secretive lessons forced upon her by her mother. She quickly learns to modulate her voice and behavior to pacify her volatile father, desperate for a place of genuine acceptance.

Schaffa is a former Guardian who suffers severe memory loss and chronic physical pain managed by a metallic implant in his brainstem. He retains his core instincts for gathering orogenes but wishes to amend his past brutalities. He establishes a base at the Found Moon comm to shelter young orogenes and takes a special interest in Nassun.

Ykka is the self-taught orogene headwoman of Castrima. She manages a tenuous peace between stills and orogenes in an underground ruin using functional, unrefined orogeny. She prioritizes the survival of her community as a whole rather than focusing solely on individual preservation.

Jija is a traveling stoneknapper searching for a rumored cure for orogeny. He harbors a deeply ingrained hatred for individuals with seismic abilities due to witnessing a childhood tragedy. He lives in a state of continuous cognitive dissonance, functioning as a guardian to his daughter while despising her fundamental nature.

Alabaster is an extraordinarily powerful Fulcrum-trained orogene responsible for triggering the current apocalyptic Season. He suffers from a terminal condition that turns his flesh to stone as a direct consequence of his immense power usage. Confined to a bed, he spends his waking hours instructing Essun on how to harness planetary magic.

Hoa is an ancient stone eater who acts as the primary narrator of the story. He initially presents as a pale, human-like child who follows Essun through the underground comm. He possesses hidden motives regarding the ongoing war between his kind and humanity, though he acts as a direct protector to Essun.

Tonkee is a knowledgeable traveler from the Leadership caste who relies on scientific inquiry rather than traditional stonelore. She studies deadciv ruins and floating obelisks, frequently attempting to uncover the truth hidden within historical propaganda. She aggressively pursues knowledge regardless of the immediate danger.

Lerna is the dedicated comm doctor in Castrima. He struggles under the immense pressure of triaging patients when medical resources and basic survival supplies are strictly rationed. He seeks solace from the harsh realities of his profession in quiet moments with Essun.

Steel is a gray-skinned stone eater with a nihilistic agenda regarding the planetary crisis. He tracks Nassun down to manipulate her growing power and deep-seated resentment. He actively believes that the planet's equilibrium can only be restored through absolute destruction.

Uche is the young son of Essun and Jija. His sudden manifestation of orogenic abilities shatters his family's quiet life, serving as the violent catalyst for the events that split his parents apart.

Antimony is a taciturn stone eater who watches over Alabaster. She acts as a quiet liaison between Alabaster and the deep-earth history he uncovered during his time in the deadciv city of Corepoint.

Hjarka is a strong-willed member of Castrima's Leadership caste. She participates in governance but remains highly suspicious of the orogenes living openly within the comm, frequently voicing the prejudices common among stills.

Cutter is a Castrima resident who recently discovered and disclosed his own minor orogenic abilities. He attempts to help maintain order during the comm's frequent logistical crises.

Umber is a Guardian stationed at the Found Moon settlement. He monitors the orogene children with severe discipline and harbors growing suspicions regarding Schaffa's unconventional methods and particular interest in Nassun.

Litz is an older man from a coastal settlement who discovers a severely injured Guardian on the beach. He provides basic medical care and shelter, unaware of the danger his guest poses to his family.

Eitz is a young orogene boy terrified of his own powers and the possibility of discovery. His mere presence inadvertently triggers a deeply conditioned, violent instinct in the recovering Guardian resting in his home.