A bygone is a creature of myth and legend that can no longer exist openly on Earth due to its incompatibility with the Consensus. The rarest and mightiest of the bygones cannot exist on Earth at all, only in the Umbra; their very existence is incompatible with the Consensus, and they accrue paradox while on Earth.
In the modern era, bygones are usually only seen on Earth if brought there by mages; many of them have become familiars or custos, and are often allied with Dreamspeakers or Verbena. They are often found on Earth in the company of Marauders, whose dynamic Quiets are strong enough to overpower the Consensus enough that bygones can exist on Earth in the affected area for a while.
Bygones are not to be confused with Umbrood or other spirits, which are Umbral creatures formed wholly of spirit, or with chimerae, which are creatures of the Dreaming.
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