Ryo and Ezio reached Kaer Morhen after an early childhood beyond the borderlands. They trained and lived as witchers.

Ezio and Ryo became vampires as adults through separate near-death events.

Kiba guided or lured Ryo and Ezio toward Olympus so the brothers could absorb the powers of gods. He did not do this from desperation for more power.

Vina Villa is protected by a shifting labyrinth modeled after the labyrinth of Crete. It provides a safe route when no threat is detected, but may produce traps and minor Greek monsters when intruders are classified as dangerous.

Hostile Watchers are established threats within the archive. Ryo has eliminated multiple hostile Watchers and used Igni to burn the remains during cleanup.

Ryo and Ezio have fought gods in other universes.

Kiba discovered that revealing his unrestrained presence prevented ordinary beings from remaining close enough to become useful. Inside an unnamed inn, he observed how mortals concealed fear, resentment, intention, and discomfort beneath courtesy. He did not learn humanity there. He learned which version of himself humanity would allow through the door.