01
Definition
A universal constant is not merely something extraordinarily durable. Its Root Signature is an invariant of reality. No ordinary revision to a timeline or destruction of a world can make that Signature permanently nonexistent.
Only two such existences are currently established in the lore: Lunor Soryn and the Eclipse Sanctum. Their constancy is a property of existence, not a declaration that they can perform every action.
02
Persistence versus invulnerability
A physical manifestation of a constant may be harmed, removed, or restrained. Memories, knowledge, access to Lumen, and relationships may be altered. The underlying identity remains, and restoration or another manifestation can eventually be possible without an assured timetable.
03
Singularity
Each constant has one true fundamental Signature. Timeline branches do not independently manufacture duplicate constants. Apparitions, memories, echoes, and non-simultaneous appearances may exist, but none creates a second autonomous Lunor.
04
Open questions
It is not yet established whether additional constants can be made, whether the Sanctum was ever different before retroactive correction, or whether a universal constant can voluntarily surrender its status. These should remain mysteries until deliberately canonized.